Tag Archives: algorithms

Looking Forward to 2018

Post Syndicated from Let's Encrypt - Free SSL/TLS Certificates original https://letsencrypt.org//2017/12/07/looking-forward-to-2018.html

Let’s Encrypt had a great year in 2017. We more than doubled the number of active (unexpired) certificates we service to 46 million, we just about tripled the number of unique domains we service to 61 million, and we did it all while maintaining a stellar security and compliance track record. Most importantly though, the Web went from 46% encrypted page loads to 67% according to statistics from Mozilla – a gain of 21% in a single year – incredible. We’re proud to have contributed to that, and we’d like to thank all of the other people and organizations who also worked hard to create a more secure and privacy-respecting Web.

While we’re proud of what we accomplished in 2017, we are spending most of the final quarter of the year looking forward rather than back. As we wrap up our own planning process for 2018, I’d like to share some of our plans with you, including both the things we’re excited about and the challenges we’ll face. We’ll cover service growth, new features, infrastructure, and finances.

Service Growth

We are planning to double the number of active certificates and unique domains we service in 2018, to 90 million and 120 million, respectively. This anticipated growth is due to continuing high expectations for HTTPS growth in general in 2018.

Let’s Encrypt helps to drive HTTPS adoption by offering a free, easy to use, and globally available option for obtaining the certificates required to enable HTTPS. HTTPS adoption on the Web took off at an unprecedented rate from the day Let’s Encrypt launched to the public.

One of the reasons Let’s Encrypt is so easy to use is that our community has done great work making client software that works well for a wide variety of platforms. We’d like to thank everyone involved in the development of over 60 client software options for Let’s Encrypt. We’re particularly excited that support for the ACME protocol and Let’s Encrypt is being added to the Apache httpd server.

Other organizations and communities are also doing great work to promote HTTPS adoption, and thus stimulate demand for our services. For example, browsers are starting to make their users more aware of the risks associated with unencrypted HTTP (e.g. Firefox, Chrome). Many hosting providers and CDNs are making it easier than ever for all of their customers to use HTTPS. Government agencies are waking up to the need for stronger security to protect constituents. The media community is working to Secure the News.

New Features

We’ve got some exciting features planned for 2018.

First, we’re planning to introduce an ACME v2 protocol API endpoint and support for wildcard certificates along with it. Wildcard certificates will be free and available globally just like our other certificates. We are planning to have a public test API endpoint up by January 4, and we’ve set a date for the full launch: Tuesday, February 27.

Later in 2018 we plan to introduce ECDSA root and intermediate certificates. ECDSA is generally considered to be the future of digital signature algorithms on the Web due to the fact that it is more efficient than RSA. Let’s Encrypt will currently sign ECDSA keys from subscribers, but we sign with the RSA key from one of our intermediate certificates. Once we have an ECDSA root and intermediates, our subscribers will be able to deploy certificate chains which are entirely ECDSA.

Infrastructure

Our CA infrastructure is capable of issuing millions of certificates per day with multiple redundancy for stability and a wide variety of security safeguards, both physical and logical. Our infrastructure also generates and signs nearly 20 million OCSP responses daily, and serves those responses nearly 2 billion times per day. We expect issuance and OCSP numbers to double in 2018.

Our physical CA infrastructure currently occupies approximately 70 units of rack space, split between two datacenters, consisting primarily of compute servers, storage, HSMs, switches, and firewalls.

When we issue more certificates it puts the most stress on storage for our databases. We regularly invest in more and faster storage for our database servers, and that will continue in 2018.

We’ll need to add a few additional compute servers in 2018, and we’ll also start aging out hardware in 2018 for the first time since we launched. We’ll age out about ten 2u compute servers and replace them with new 1u servers, which will save space and be more energy efficient while providing better reliability and performance.

We’ll also add another infrastructure operations staff member, bringing that team to a total of six people. This is necessary in order to make sure we can keep up with demand while maintaining a high standard for security and compliance. Infrastructure operations staff are systems administrators responsible for building and maintaining all physical and logical CA infrastructure. The team also manages a 24/7/365 on-call schedule and they are primary participants in both security and compliance audits.

Finances

We pride ourselves on being an efficient organization. In 2018 Let’s Encrypt will secure a large portion of the Web with a budget of only $3.0M. For an overall increase in our budget of only 13%, we will be able to issue and service twice as many certificates as we did in 2017. We believe this represents an incredible value and that contributing to Let’s Encrypt is one of the most effective ways to help create a more secure and privacy-respecting Web.

Our 2018 fundraising efforts are off to a strong start with Platinum sponsorships from Mozilla, Akamai, OVH, Cisco, Google Chrome and the Electronic Frontier Foundation. The Ford Foundation has renewed their grant to Let’s Encrypt as well. We are seeking additional sponsorship and grant assistance to meet our full needs for 2018.

We had originally budgeted $2.91M for 2017 but we’ll likely come in under budget for the year at around $2.65M. The difference between our 2017 expenses of $2.65M and the 2018 budget of $3.0M consists primarily of the additional infrastructure operations costs previously mentioned.

Support Let’s Encrypt

We depend on contributions from our community of users and supporters in order to provide our services. If your company or organization would like to sponsor Let’s Encrypt please email us at [email protected]. We ask that you make an individual contribution if it is within your means.

We’re grateful for the industry and community support that we receive, and we look forward to continuing to create a more secure and privacy-respecting Web!

Implementing Dynamic ETL Pipelines Using AWS Step Functions

Post Syndicated from Tara Van Unen original https://aws.amazon.com/blogs/compute/implementing-dynamic-etl-pipelines-using-aws-step-functions/

This post contributed by:
Wangechi Dole, AWS Solutions Architect
Milan Krasnansky, ING, Digital Solutions Developer, SGK
Rian Mookencherry, Director – Product Innovation, SGK

Data processing and transformation is a common use case you see in our customer case studies and success stories. Often, customers deal with complex data from a variety of sources that needs to be transformed and customized through a series of steps to make it useful to different systems and stakeholders. This can be difficult due to the ever-increasing volume, velocity, and variety of data. Today, data management challenges cannot be solved with traditional databases.

Workflow automation helps you build solutions that are repeatable, scalable, and reliable. You can use AWS Step Functions for this. A great example is how SGK used Step Functions to automate the ETL processes for their client. With Step Functions, SGK has been able to automate changes within the data management system, substantially reducing the time required for data processing.

In this post, SGK shares the details of how they used Step Functions to build a robust data processing system based on highly configurable business transformation rules for ETL processes.

SGK: Building dynamic ETL pipelines

SGK is a subsidiary of Matthews International Corporation, a diversified organization focusing on brand solutions and industrial technologies. SGK’s Global Content Creation Studio network creates compelling content and solutions that connect brands and products to consumers through multiple assets including photography, video, and copywriting.

We were recently contracted to build a sophisticated and scalable data management system for one of our clients. We chose to build the solution on AWS to leverage advanced, managed services that help to improve the speed and agility of development.

The data management system served two main functions:

  1. Ingesting a large amount of complex data to facilitate both reporting and product funding decisions for the client’s global marketing and supply chain organizations.
  2. Processing the data through normalization and applying complex algorithms and data transformations. The system goal was to provide information in the relevant context—such as strategic marketing, supply chain, product planning, etc. —to the end consumer through automated data feeds or updates to existing ETL systems.

We were faced with several challenges:

  • Output data that needed to be refreshed at least twice a day to provide fresh datasets to both local and global markets. That constant data refresh posed several challenges, especially around data management and replication across multiple databases.
  • The complexity of reporting business rules that needed to be updated on a constant basis.
  • Data that could not be processed as contiguous blocks of typical time-series data. The measurement of the data was done across seasons (that is, combination of dates), which often resulted with up to three overlapping seasons at any given time.
  • Input data that came from 10+ different data sources. Each data source ranged from 1–20K rows with as many as 85 columns per input source.

These challenges meant that our small Dev team heavily invested time in frequent configuration changes to the system and data integrity verification to make sure that everything was operating properly. Maintaining this system proved to be a daunting task and that’s when we turned to Step Functions—along with other AWS services—to automate our ETL processes.

Solution overview

Our solution included the following AWS services:

  • AWS Step Functions: Before Step Functions was available, we were using multiple Lambda functions for this use case and running into memory limit issues. With Step Functions, we can execute steps in parallel simultaneously, in a cost-efficient manner, without running into memory limitations.
  • AWS Lambda: The Step Functions state machine uses Lambda functions to implement the Task states. Our Lambda functions are implemented in Java 8.
  • Amazon DynamoDB provides us with an easy and flexible way to manage business rules. We specify our rules as Keys. These are key-value pairs stored in a DynamoDB table.
  • Amazon RDS: Our ETL pipelines consume source data from our RDS MySQL database.
  • Amazon Redshift: We use Amazon Redshift for reporting purposes because it integrates with our BI tools. Currently we are using Tableau for reporting which integrates well with Amazon Redshift.
  • Amazon S3: We store our raw input files and intermediate results in S3 buckets.
  • Amazon CloudWatch Events: Our users expect results at a specific time. We use CloudWatch Events to trigger Step Functions on an automated schedule.

Solution architecture

This solution uses a declarative approach to defining business transformation rules that are applied by the underlying Step Functions state machine as data moves from RDS to Amazon Redshift. An S3 bucket is used to store intermediate results. A CloudWatch Event rule triggers the Step Functions state machine on a schedule. The following diagram illustrates our architecture:

Here are more details for the above diagram:

  1. A rule in CloudWatch Events triggers the state machine execution on an automated schedule.
  2. The state machine invokes the first Lambda function.
  3. The Lambda function deletes all existing records in Amazon Redshift. Depending on the dataset, the Lambda function can create a new table in Amazon Redshift to hold the data.
  4. The same Lambda function then retrieves Keys from a DynamoDB table. Keys represent specific marketing campaigns or seasons and map to specific records in RDS.
  5. The state machine executes the second Lambda function using the Keys from DynamoDB.
  6. The second Lambda function retrieves the referenced dataset from RDS. The records retrieved represent the entire dataset needed for a specific marketing campaign.
  7. The second Lambda function executes in parallel for each Key retrieved from DynamoDB and stores the output in CSV format temporarily in S3.
  8. Finally, the Lambda function uploads the data into Amazon Redshift.

To understand the above data processing workflow, take a closer look at the Step Functions state machine for this example.

We walk you through the state machine in more detail in the following sections.

Walkthrough

To get started, you need to:

  • Create a schedule in CloudWatch Events
  • Specify conditions for RDS data extracts
  • Create Amazon Redshift input files
  • Load data into Amazon Redshift

Step 1: Create a schedule in CloudWatch Events
Create rules in CloudWatch Events to trigger the Step Functions state machine on an automated schedule. The following is an example cron expression to automate your schedule:

In this example, the cron expression invokes the Step Functions state machine at 3:00am and 2:00pm (UTC) every day.

Step 2: Specify conditions for RDS data extracts
We use DynamoDB to store Keys that determine which rows of data to extract from our RDS MySQL database. An example Key is MCS2017, which stands for, Marketing Campaign Spring 2017. Each campaign has a specific start and end date and the corresponding dataset is stored in RDS MySQL. A record in RDS contains about 600 columns, and each Key can represent up to 20K records.

A given day can have multiple campaigns with different start and end dates running simultaneously. In the following example DynamoDB item, three campaigns are specified for the given date.

The state machine example shown above uses Keys 31, 32, and 33 in the first ChoiceState and Keys 21 and 22 in the second ChoiceState. These keys represent marketing campaigns for a given day. For example, on Monday, there are only two campaigns requested. The ChoiceState with Keys 21 and 22 is executed. If three campaigns are requested on Tuesday, for example, then ChoiceState with Keys 31, 32, and 33 is executed. MCS2017 can be represented by Key 21 and Key 33 on Monday and Tuesday, respectively. This approach gives us the flexibility to add or remove campaigns dynamically.

Step 3: Create Amazon Redshift input files
When the state machine begins execution, the first Lambda function is invoked as the resource for FirstState, represented in the Step Functions state machine as follows:

"Comment": ” AWS Amazon States Language.", 
  "StartAt": "FirstState",
 
"States": { 
  "FirstState": {
   
"Type": "Task",
   
"Resource": "arn:aws:lambda:xx-xxxx-x:XXXXXXXXXXXX:function:Start",
    "Next": "ChoiceState" 
  } 

As described in the solution architecture, the purpose of this Lambda function is to delete existing data in Amazon Redshift and retrieve keys from DynamoDB. In our use case, we found that deleting existing records was more efficient and less time-consuming than finding the delta and updating existing records. On average, an Amazon Redshift table can contain about 36 million cells, which translates to roughly 65K records. The following is the code snippet for the first Lambda function in Java 8:

public class LambdaFunctionHandler implements RequestHandler<Map<String,Object>,Map<String,String>> {
    Map<String,String> keys= new HashMap<>();
    public Map<String, String> handleRequest(Map<String, Object> input, Context context){
       Properties config = getConfig(); 
       // 1. Cleaning Redshift Database
       new RedshiftDataService(config).cleaningTable(); 
       // 2. Reading data from Dynamodb
       List<String> keyList = new DynamoDBDataService(config).getCurrentKeys();
       for(int i = 0; i < keyList.size(); i++) {
           keys.put(”key" + (i+1), keyList.get(i)); 
       }
       keys.put(”key" + T,String.valueOf(keyList.size()));
       // 3. Returning the key values and the key count from the “for” loop
       return (keys);
}

The following JSON represents ChoiceState.

"ChoiceState": {
   "Type" : "Choice",
   "Choices": [ 
   {

      "Variable": "$.keyT",
     "StringEquals": "3",
     "Next": "CurrentThreeKeys" 
   }, 
   {

     "Variable": "$.keyT",
    "StringEquals": "2",
    "Next": "CurrentTwooKeys" 
   } 
 ], 
 "Default": "DefaultState"
}

The variable $.keyT represents the number of keys retrieved from DynamoDB. This variable determines which of the parallel branches should be executed. At the time of publication, Step Functions does not support dynamic parallel state. Therefore, choices under ChoiceState are manually created and assigned hardcoded StringEquals values. These values represent the number of parallel executions for the second Lambda function.

For example, if $.keyT equals 3, the second Lambda function is executed three times in parallel with keys, $key1, $key2 and $key3 retrieved from DynamoDB. Similarly, if $.keyT equals two, the second Lambda function is executed twice in parallel.  The following JSON represents this parallel execution:

"CurrentThreeKeys": { 
  "Type": "Parallel",
  "Next": "NextState",
  "Branches": [ 
  {

     "StartAt": “key31",
    "States": { 
       “key31": {

          "Type": "Task",
        "InputPath": "$.key1",
        "Resource": "arn:aws:lambda:xx-xxxx-x:XXXXXXXXXXXX:function:Execution",
        "End": true 
       } 
    } 
  }, 
  {

     "StartAt": “key32",
    "States": { 
     “key32": {

        "Type": "Task",
       "InputPath": "$.key2",
         "Resource": "arn:aws:lambda:xx-xxxx-x:XXXXXXXXXXXX:function:Execution",
       "End": true 
      } 
     } 
   }, 
   {

      "StartAt": “key33",
       "States": { 
          “key33": {

                "Type": "Task",
             "InputPath": "$.key3",
             "Resource": "arn:aws:lambda:xx-xxxx-x:XXXXXXXXXXXX:function:Execution",
           "End": true 
       } 
     } 
    } 
  ] 
} 

Step 4: Load data into Amazon Redshift
The second Lambda function in the state machine extracts records from RDS associated with keys retrieved for DynamoDB. It processes the data then loads into an Amazon Redshift table. The following is code snippet for the second Lambda function in Java 8.

public class LambdaFunctionHandler implements RequestHandler<String, String> {
 public static String key = null;

public String handleRequest(String input, Context context) { 
   key=input; 
   //1. Getting basic configurations for the next classes + s3 client Properties
   config = getConfig();

   AmazonS3 s3 = AmazonS3ClientBuilder.defaultClient(); 
   // 2. Export query results from RDS into S3 bucket 
   new RdsDataService(config).exportDataToS3(s3,key); 
   // 3. Import query results from S3 bucket into Redshift 
    new RedshiftDataService(config).importDataFromS3(s3,key); 
   System.out.println(input); 
   return "SUCCESS"; 
 } 
}

After the data is loaded into Amazon Redshift, end users can visualize it using their preferred business intelligence tools.

Lessons learned

  • At the time of publication, the 1.5–GB memory hard limit for Lambda functions was inadequate for processing our complex workload. Step Functions gave us the flexibility to chunk our large datasets and process them in parallel, saving on costs and time.
  • In our previous implementation, we assigned each key a dedicated Lambda function along with CloudWatch rules for schedule automation. This approach proved to be inefficient and quickly became an operational burden. Previously, we processed each key sequentially, with each key adding about five minutes to the overall processing time. For example, processing three keys meant that the total processing time was three times longer. With Step Functions, the entire state machine executes in about five minutes.
  • Using DynamoDB with Step Functions gave us the flexibility to manage keys efficiently. In our previous implementations, keys were hardcoded in Lambda functions, which became difficult to manage due to frequent updates. DynamoDB is a great way to store dynamic data that changes frequently, and it works perfectly with our serverless architectures.

Conclusion

With Step Functions, we were able to fully automate the frequent configuration updates to our dataset resulting in significant cost savings, reduced risk to data errors due to system downtime, and more time for us to focus on new product development rather than support related issues. We hope that you have found the information useful and that it can serve as a jump-start to building your own ETL processes on AWS with managed AWS services.

For more information about how Step Functions makes it easy to coordinate the components of distributed applications and microservices in any workflow, see the use case examples and then build your first state machine in under five minutes in the Step Functions console.

If you have questions or suggestions, please comment below.

Presenting Amazon Sumerian: An easy way to create VR, AR, and 3D experiences

Post Syndicated from Tara Walker original https://aws.amazon.com/blogs/aws/launch-presenting-amazon-sumerian/

If you have had an opportunity to read any of my blog posts or attended any session I’ve conducted at various conferences, you are probably aware that I am definitively a geek girl. I am absolutely enamored with all of the latest advancements that have been made in technology areas like cloud, artificial intelligence, internet of things and the maker space, as well as, with virtual reality and augmented reality. In my opinion, it is a wonderful time to be a geek. All the things that we dreamed about building while we sweated through our algorithms and discrete mathematics classes or the technology we marveled at when watching Star Wars and Star Trek are now coming to fruition.  So hopefully this means it will only be a matter of time before I can hyperdrive to other galaxies in space, but until then I can at least build the 3D virtual reality and augmented reality characters and images like those featured in some of my favorite shows.

Amazon Sumerian provides tools and resources that allows anyone to create and run augmented reality (AR), virtual reality (VR), and 3D applications with ease.  With Sumerian, you can build multi-platform experiences that run on hardware like the Oculus, HTC Vive, and iOS devices using WebVR compatible browsers and with support for ARCore on Android devices coming soon.

This exciting new service, currently in preview, delivers features to allow you to design highly immersive and interactive 3D experiences from your browser. Some of these features are:

  • Editor: A web-based editor for constructing 3D scenes, importing assets, scripting interactions and special effects, with cross-platform publishing.
  • Object Library: a library of pre-built objects and templates.
  • Asset Import: Upload 3D assets to use in your scene. Sumerian supports importing FBX, OBJ, and coming soon Unity projects.
  • Scripting Library: provides a JavaScript scripting library via its 3D engine for advanced scripting capabilities.
  • Hosts: animated, lifelike 3D characters that can be customized for gender, voice, and language.
  • AWS Services Integration: baked in integration with Amazon Polly and Amazon Lex to add speech and natural language to into Sumerian hosts. Additionally, the scripting library can be used with AWS Lambda allowing use of the full range of AWS services.

Since Amazon Sumerian doesn’t require you to have 3D graphics or programming experience to build rich, interactive VR and AR scenes, let’s take a quick run to the Sumerian Dashboard and check it out.

From the Sumerian Dashboard, I can easily create a new scene with a push of a button.

A default view of the new scene opens and is displayed in the Sumerian Editor. With the Tara Blog Scene opened in the editor, I can easily import assets into my scene.

I’ll click the Import Asset button and pick an asset, View Room, to import into the scene. With the desired asset selected, I’ll click the Add button to import it.

Excellent, my asset was successfully imported into the Sumerian Editor and is shown in the Asset panel.  Now, I have the option to add the View Room object into my scene by selecting it in the Asset panel and then dragging it onto the editor’s canvas.

I’ll repeat the import asset process and this time I will add the Mannequin asset to the scene.

Additionally, with Sumerian, I can add scripting to Entity assets to make my scene even more exciting by adding a ScriptComponent to an entity and creating a script.  I can use the provided built-in scripts or create my own custom scripts. If I create a new custom script, I will get a blank script with some base JavaScript code that looks similar to the code below.

'use strict';
/* global sumerian */
//This is Me-- trying out the custom scripts - Tara

var setup = function (args, ctx) {
// Called when play mode starts.
};
var fixedUpdate = function (args, ctx) {
// Called on every physics update, after setup().
};
var update = function (args, ctx) {
// Called on every render frame, after setup().
};
var lateUpdate = function (args, ctx) {
// Called after all script "update" methods in the scene has been called.
};
var cleanup = function (args, ctx) {
// Called when play mode stops.
};
var parameters = [];

Very cool, I just created a 3D scene using Amazon Sumerian in a matter of minutes and I have only scratched the surface.

Summary

The Amazon Sumerian service enables you to create, build, and run virtual reality (VR), augmented reality (AR), and 3D applications with ease.  You don’t need any 3D graphics or specialized programming knowledge to get started building scenes and immersive experiences.  You can import FBX, OBJ, and Unity projects in Sumerian, as well as upload your own 3D assets for use in your scene. In addition, you can create digital characters to narrate your scene and with these digital assets, you have choices for the character’s appearance, speech and behavior.

You can learn more about Amazon Sumerian and sign up for the preview to get started with the new service on the product page.  I can’t wait to see what rich experiences you all will build.

Tara

 

Amazon and Microsoft Ramp Up their AI Efforts

Post Syndicated from Chris De Santis original https://www.anchor.com.au/blog/2017/11/amazon-microsoft-ai-efforts/

In recent years, Amazon Web Services and Microsoft have shifted to more of a focus on artificial intelligence (AI), and as a result, have vastly increased their investment in the implementation and advancement of AI over their fleets of online products and services.

Recently, at Sydney’s Microsoft Summit (16-17 November 2017), Microsoft announced that they have stepped up their investment in the AI arena by releasing and showcasing new tools to enhance human and organisational capabilities. These tools include Visual Studio Tools for AI, Azure IoT Edge, Microsoft Translator, and Seeing AI.

The reasoning that Microsoft gave to justify their focus is that the popularity of AI has been steadily increasing, which can be attributed to three main factors: cloud computing, powerful algorithms, and multitudes of data.

Amazon, on the other hand, are planning to introduce a number of new AI products into the market, in order to catch up to the likes of Microsoft and Google. Through a project codenamed “Ironman”, AWS are working internally as well as partnering with startups to take a few-years-old AWS data warehousing service and gearing it to organise data for workloads employing machine learning techniques.

For more information more information on recent AI endeavours in the cloud computing market, check out our previous article below:

AI in the Cloud Market: AWS & Microsoft Lend a Big Hand

Amazon and Microsoft Ramp Up their AI Efforts

The post Amazon and Microsoft Ramp Up their AI Efforts appeared first on AWS Managed Services by Anchor.

Fraud Detection in Pokémon Go

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/11/fraud_detection.html

I play Pokémon Go. (There, I’ve admitted it.) One of the interesting aspects of the game I’ve been watching is how the game’s publisher, Niantec, deals with cheaters.

There are three basic types of cheating in Pokémon Go. The first is botting, where a computer plays the game instead of a person. The second is spoofing, which is faking GPS to convince the game that you’re somewhere you’re not. These two cheats are often used together — and you see the results in the many high-level accounts for sale on the Internet. The third type of cheating is the use of third-party apps like trackers to get extra information about the game.

None of this would matter if everyone played independently. The only reason any player cares about whether other players are cheating is that there is a group aspect of the game: gym battling. Everyone’s enjoyment of that part of the game is affected by cheaters who can pretend to be where they’re not, especially if they have lots of powerful Pokémon that they collected effortlessly.

Niantec has been trying to deal with this problem since the game debuted, mostly by banning accounts when it detects cheating. Its initial strategy was basic — algorithmically detecting impossibly fast travel between physical locations or super-human amounts of playing, and then banning those accounts — with limited success. The limiting factor in all of this is false positives. While Niantec wants to stop cheating, it doesn’t want to block or limit any legitimate players. This makes it a very difficult problem, and contributes to the balance in the attacker/defender arms race.

Recently, Niantic implemented two new anti-cheating measures. The first is machine learning to detect cheaters. About this, we know little. The second is to limit the functionality of cheating accounts rather than ban them outright, making it harder for cheaters to know when they’ve been discovered.

“This is may very well be the beginning of Niantic’s machine learning approach to active bot countering,” user Dronpes writes on The Silph Road subreddit. “If the parameters for a shadowban are constantly adjusted server-side, as they can now easily be, then Niantic’s machine learning engineers can train their detection (classification) algorithms in ever-improving, ever more aggressive ways, and botters will constantly be forced to re-evaluate what factors may be triggering the detection.”

One of the expected future features in the game is trading. Creating a market for rare or powerful Pokémon would add a huge additional financial incentive to cheat. Unless Niantec can effectively prevent botting and spoofing, it’s unlikely to implement that feature.

Cheating detection in virtual reality games is going to be a constant problem as these games become more popular, especially if there are ways to monetize the results of cheating. This means that cheater detection will continue to be a critical component of these games’ success. Anything Niantec learns in Pokémon Go will be useful in whatever games come next.

Mystic, level 39 — if you must know.

And, yes, I know the game tracks works by tracking your location. I’m all right with that. As I repeatedly say, Internet privacy is all about trade-offs.

Google Asked to Remove 3 Billion “Pirate” Search Results

Post Syndicated from Ernesto original https://torrentfreak.com/google-asked-to-remove-3-billion-pirate-search-results-171018/

Copyright holders continue to flood Google with DMCA takedown requests, asking the company to remove “pirate links” from its search results.

In recent years the number of reported URLs has exploded, surging to unprecedented heights.

Since Google first started to report the volume of takedown requests in its Transparency Report, the company has been asked to remove more than three billion allegedly infringing search results.

The frequency at which these URLs are reported has increased over the years and at the moment roughly three million ‘pirate’ URLs are submitted per day.

The URLs are sent in by major rightsholders including members of the BPI, RIAA, and various major Hollywood studios. They target a wide variety of sites, over 1.3 million, but a few dozen ‘repeat offenders’ are causing the most trouble.

File-hosting service 4shared.com currently tops the list of most-targeted domains with 66 million URLs, followed by the now-defunct MP3 download site MP3toys.xyz and Rapidgator.net, with 51 and 28 million URLs respectively.

3 billion URLs

Interestingly, the high volume of takedown notices is used as an argument for and against the DMCA process.

While Google believes that the millions of reported URLs per day are a sign that the DMCA takedown process is working correctly, rightsholders believe the volumes are indicative of an unbeatable game of whack-a-mole.

According to some copyright holders, the takedown efforts do little to seriously combat piracy. Various industry groups have therefore asked governments and lawmakers for broad revisions.

Among other things they want advanced technologies and processes to ensure that infringing content doesn’t reappear elsewhere once it’s removed, a so-called “notice and stay down” approach. In addition, Google has often been asked to demote pirate links in search results.

UK music industry group BPI, who are responsible for more than 10% of all the takedown requests on Google, sees the new milestone as an indicator of how much effort its anti-piracy activities take.

“This 3 billion figure shows how hard the creative sector has to work to police its content online and how much time and resource this takes. The BPI is the world’s largest remover of illegal music links from Google, one third of which are on behalf of independent record labels,” Geoff Taylor, BPI’s Chief Executive, informs TF.

However, there is also some progress to report. Earlier this year BPI announced a voluntary partnership with Google and Bing to demote pirate content faster and more effectively for US visitors.

“We now have a voluntary code of practice in place in the UK, facilitated by Government, that requires Google and Bing to work together with the BPI and other creator organizations to develop lasting solutions to the problem of illegal sites gaining popularity in search listings,” Taylor notes.

According to BPI, both Google and Bing have shown that changes to their algorithms can be effective in demoting the worst pirate sites from the top search results and they hope others will follow suit.

“Other intermediaries should follow this lead and take more responsibility to work with creators to reduce the proliferation of illegal links and disrupt the ability of illegal sites to capture consumers and build black market businesses that take money away from creators.”

Agreement or not, there are still plenty of pirate links in search results, so the BPI is still sending out millions of takedown requests per month.

We asked Google for a comment on the new milestone but at the time of writing, we have yet to hear back. In any event, the issue is bound to remain a hot topic during the months and years to come.

Source: TF, for the latest info on copyright, file-sharing, torrent sites and ANONYMOUS VPN services.

My Blogging

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/10/my_blogging.html

Blog regulars will notice that I haven’t been posting as much lately as I have in the past. There are two reasons. One, it feels harder to find things to write about. So often it’s the same stories over and over. I don’t like repeating myself. Two, I am busy writing a book. The title is still: Click Here to Kill Everybody: Peril and Promise in a Hyper-Connected World. The book is a year late, and as a very different table of contents than it had in 2016. I have been writing steadily since mid-August. The book is due to the publisher at the end of March 2018, and will be published in the beginning of September.

This is the current table of contents:

  • Introduction: Everything is Becoming a Computer
  • Part 1: The Trends
    • 1. Capitalism Continues to Drive the Internet
    • 2. Customer/User Control is Next
    • 3. Government Surveillance and Control is Also Increasing
    • 4. Cybercrime is More Profitable Than Ever
    • 5. Cyberwar is the New Normal
    • 6. Algorithms, Automation, and Autonomy Bring New Dangers
    • 7. What We Know About Computer Security
    • 8. Agile is Failing as a Security Paradigm
    • 9. Authentication and Identification are Getting Harder
    • 10. Risks are Becoming Catastrophic
  • Part 2: The Solutions
    • 11. We Need to Regulate the Internet of Things
    • 12. We Need to Defend Critical Infrastructure
    • 13. We Need to Prioritize Defense Over Offence
    • 14. We Need to Make Smarter Decisions About Connecting
    • 15. What’s Likely to Happen, and What We Can Do in Response
    • 16. Where Policy Can Go Wrong
  • Conclusion: Technology and Policy, Together

So that’s what’s been happening.

Predict Billboard Top 10 Hits Using RStudio, H2O and Amazon Athena

Post Syndicated from Gopal Wunnava original https://aws.amazon.com/blogs/big-data/predict-billboard-top-10-hits-using-rstudio-h2o-and-amazon-athena/

Success in the popular music industry is typically measured in terms of the number of Top 10 hits artists have to their credit. The music industry is a highly competitive multi-billion dollar business, and record labels incur various costs in exchange for a percentage of the profits from sales and concert tickets.

Predicting the success of an artist’s release in the popular music industry can be difficult. One release may be extremely popular, resulting in widespread play on TV, radio and social media, while another single may turn out quite unpopular, and therefore unprofitable. Record labels need to be selective in their decision making, and predictive analytics can help them with decision making around the type of songs and artists they need to promote.

In this walkthrough, you leverage H2O.ai, Amazon Athena, and RStudio to make predictions on whether a song might make it to the Top 10 Billboard charts. You explore the GLM, GBM, and deep learning modeling techniques using H2O’s rapid, distributed and easy-to-use open source parallel processing engine. RStudio is a popular IDE, licensed either commercially or under AGPLv3, for working with R. This is ideal if you don’t want to connect to a server via SSH and use code editors such as vi to do analytics. RStudio is available in a desktop version, or a server version that allows you to access R via a web browser. RStudio’s Notebooks feature is used to demonstrate the execution of code and output. In addition, this post showcases how you can leverage Athena for query and interactive analysis during the modeling phase. A working knowledge of statistics and machine learning would be helpful to interpret the analysis being performed in this post.

Walkthrough

Your goal is to predict whether a song will make it to the Top 10 Billboard charts. For this purpose, you will be using multiple modeling techniques―namely GLM, GBM and deep learning―and choose the model that is the best fit.

This solution involves the following steps:

  • Install and configure RStudio with Athena
  • Log in to RStudio
  • Install R packages
  • Connect to Athena
  • Create a dataset
  • Create models

Install and configure RStudio with Athena

Use the following AWS CloudFormation stack to install, configure, and connect RStudio on an Amazon EC2 instance with Athena.

Launching this stack creates all required resources and prerequisites:

  • Amazon EC2 instance with Amazon Linux (minimum size of t2.large is recommended)
  • Provisioning of the EC2 instance in an existing VPC and public subnet
  • Installation of Java 8
  • Assignment of an IAM role to the EC2 instance with the required permissions for accessing Athena and Amazon S3
  • Security group allowing access to the RStudio and SSH ports from the internet (I recommend restricting access to these ports)
  • S3 staging bucket required for Athena (referenced within RStudio as ATHENABUCKET)
  • RStudio username and password
  • Setup logs in Amazon CloudWatch Logs (if needed for additional troubleshooting)
  • Amazon EC2 Systems Manager agent, which makes it easy to manage and patch

All AWS resources are created in the US-East-1 Region. To avoid cross-region data transfer fees, launch the CloudFormation stack in the same region. To check the availability of Athena in other regions, see Region Table.

Log in to RStudio

The instance security group has been automatically configured to allow incoming connections on the RStudio port 8787 from any source internet address. You can edit the security group to restrict source IP access. If you have trouble connecting, ensure that port 8787 isn’t blocked by subnet network ACLS or by your outgoing proxy/firewall.

  1. In the CloudFormation stack, choose Outputs, Value, and then open the RStudio URL. You might need to wait for a few minutes until the instance has been launched.
  2. Log in to RStudio with the and password you provided during setup.

Install R packages

Next, install the required R packages from the RStudio console. You can download the R notebook file containing just the code.

#install pacman – a handy package manager for managing installs
if("pacman" %in% rownames(installed.packages()) == FALSE)
{install.packages("pacman")}  
library(pacman)
p_load(h2o,rJava,RJDBC,awsjavasdk)
h2o.init(nthreads = -1)
##  Connection successful!
## 
## R is connected to the H2O cluster: 
##     H2O cluster uptime:         2 hours 42 minutes 
##     H2O cluster version:        3.10.4.6 
##     H2O cluster version age:    4 months and 4 days !!! 
##     H2O cluster name:           H2O_started_from_R_rstudio_hjx881 
##     H2O cluster total nodes:    1 
##     H2O cluster total memory:   3.30 GB 
##     H2O cluster total cores:    4 
##     H2O cluster allowed cores:  4 
##     H2O cluster healthy:        TRUE 
##     H2O Connection ip:          localhost 
##     H2O Connection port:        54321 
##     H2O Connection proxy:       NA 
##     H2O Internal Security:      FALSE 
##     R Version:                  R version 3.3.3 (2017-03-06)
## Warning in h2o.clusterInfo(): 
## Your H2O cluster version is too old (4 months and 4 days)!
## Please download and install the latest version from http://h2o.ai/download/
#install aws sdk if not present (pre-requisite for using Athena with an IAM role)
if (!aws_sdk_present()) {
  install_aws_sdk()
}

load_sdk()
## NULL

Connect to Athena

Next, establish a connection to Athena from RStudio, using an IAM role associated with your EC2 instance. Use ATHENABUCKET to specify the S3 staging directory.

URL <- 'https://s3.amazonaws.com/athena-downloads/drivers/AthenaJDBC41-1.0.1.jar'
fil <- basename(URL)
#download the file into current working directory
if (!file.exists(fil)) download.file(URL, fil)
#verify that the file has been downloaded successfully
list.files()
## [1] "AthenaJDBC41-1.0.1.jar"
drv <- JDBC(driverClass="com.amazonaws.athena.jdbc.AthenaDriver", fil, identifier.quote="'")

con <- jdbcConnection <- dbConnect(drv, 'jdbc:awsathena://athena.us-east-1.amazonaws.com:443/',
                                   s3_staging_dir=Sys.getenv("ATHENABUCKET"),
                                   aws_credentials_provider_class="com.amazonaws.auth.DefaultAWSCredentialsProviderChain")

Verify the connection. The results returned depend on your specific Athena setup.

con
## <JDBCConnection>
dbListTables(con)
##  [1] "gdelt"               "wikistats"           "elb_logs_raw_native"
##  [4] "twitter"             "twitter2"            "usermovieratings"   
##  [7] "eventcodes"          "events"              "billboard"          
## [10] "billboardtop10"      "elb_logs"            "gdelthist"          
## [13] "gdeltmaster"         "twitter"             "twitter3"

Create a dataset

For this analysis, you use a sample dataset combining information from Billboard and Wikipedia with Echo Nest data in the Million Songs Dataset. Upload this dataset into your own S3 bucket. The table below provides a description of the fields used in this dataset.

Field Description
year Year that song was released
songtitle Title of the song
artistname Name of the song artist
songid Unique identifier for the song
artistid Unique identifier for the song artist
timesignature Variable estimating the time signature of the song
timesignature_confidence Confidence in the estimate for the timesignature
loudness Continuous variable indicating the average amplitude of the audio in decibels
tempo Variable indicating the estimated beats per minute of the song
tempo_confidence Confidence in the estimate for tempo
key Variable with twelve levels indicating the estimated key of the song (C, C#, B)
key_confidence Confidence in the estimate for key
energy Variable that represents the overall acoustic energy of the song, using a mix of features such as loudness
pitch Continuous variable that indicates the pitch of the song
timbre_0_min thru timbre_11_min Variables that indicate the minimum values over all segments for each of the twelve values in the timbre vector
timbre_0_max thru timbre_11_max Variables that indicate the maximum values over all segments for each of the twelve values in the timbre vector
top10 Indicator for whether or not the song made it to the Top 10 of the Billboard charts (1 if it was in the top 10, and 0 if not)

Create an Athena table based on the dataset

In the Athena console, select the default database, sampled, or create a new database.

Run the following create table statement.

create external table if not exists billboard
(
year int,
songtitle string,
artistname string,
songID string,
artistID string,
timesignature int,
timesignature_confidence double,
loudness double,
tempo double,
tempo_confidence double,
key int,
key_confidence double,
energy double,
pitch double,
timbre_0_min double,
timbre_0_max double,
timbre_1_min double,
timbre_1_max double,
timbre_2_min double,
timbre_2_max double,
timbre_3_min double,
timbre_3_max double,
timbre_4_min double,
timbre_4_max double,
timbre_5_min double,
timbre_5_max double,
timbre_6_min double,
timbre_6_max double,
timbre_7_min double,
timbre_7_max double,
timbre_8_min double,
timbre_8_max double,
timbre_9_min double,
timbre_9_max double,
timbre_10_min double,
timbre_10_max double,
timbre_11_min double,
timbre_11_max double,
Top10 int
)
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ','
STORED AS TEXTFILE
LOCATION 's3://aws-bigdata-blog/artifacts/predict-billboard/data'
;

Inspect the table definition for the ‘billboard’ table that you have created. If you chose a database other than sampledb, replace that value with your choice.

dbGetQuery(con, "show create table sampledb.billboard")
##                                      createtab_stmt
## 1       CREATE EXTERNAL TABLE `sampledb.billboard`(
## 2                                       `year` int,
## 3                               `songtitle` string,
## 4                              `artistname` string,
## 5                                  `songid` string,
## 6                                `artistid` string,
## 7                              `timesignature` int,
## 8                `timesignature_confidence` double,
## 9                                `loudness` double,
## 10                                  `tempo` double,
## 11                       `tempo_confidence` double,
## 12                                       `key` int,
## 13                         `key_confidence` double,
## 14                                 `energy` double,
## 15                                  `pitch` double,
## 16                           `timbre_0_min` double,
## 17                           `timbre_0_max` double,
## 18                           `timbre_1_min` double,
## 19                           `timbre_1_max` double,
## 20                           `timbre_2_min` double,
## 21                           `timbre_2_max` double,
## 22                           `timbre_3_min` double,
## 23                           `timbre_3_max` double,
## 24                           `timbre_4_min` double,
## 25                           `timbre_4_max` double,
## 26                           `timbre_5_min` double,
## 27                           `timbre_5_max` double,
## 28                           `timbre_6_min` double,
## 29                           `timbre_6_max` double,
## 30                           `timbre_7_min` double,
## 31                           `timbre_7_max` double,
## 32                           `timbre_8_min` double,
## 33                           `timbre_8_max` double,
## 34                           `timbre_9_min` double,
## 35                           `timbre_9_max` double,
## 36                          `timbre_10_min` double,
## 37                          `timbre_10_max` double,
## 38                          `timbre_11_min` double,
## 39                          `timbre_11_max` double,
## 40                                     `top10` int)
## 41                             ROW FORMAT DELIMITED 
## 42                         FIELDS TERMINATED BY ',' 
## 43                            STORED AS INPUTFORMAT 
## 44       'org.apache.hadoop.mapred.TextInputFormat' 
## 45                                     OUTPUTFORMAT 
## 46  'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat'
## 47                                        LOCATION
## 48    's3://aws-bigdata-blog/artifacts/predict-billboard/data'
## 49                                  TBLPROPERTIES (
## 50            'transient_lastDdlTime'='1505484133')

Run a sample query

Next, run a sample query to obtain a list of all songs from Janet Jackson that made it to the Billboard Top 10 charts.

dbGetQuery(con, " SELECT songtitle,artistname,top10   FROM sampledb.billboard WHERE lower(artistname) =     'janet jackson' AND top10 = 1")
##                       songtitle    artistname top10
## 1                       Runaway Janet Jackson     1
## 2               Because Of Love Janet Jackson     1
## 3                         Again Janet Jackson     1
## 4                            If Janet Jackson     1
## 5  Love Will Never Do (Without You) Janet Jackson 1
## 6                     Black Cat Janet Jackson     1
## 7               Come Back To Me Janet Jackson     1
## 8                       Alright Janet Jackson     1
## 9                      Escapade Janet Jackson     1
## 10                Rhythm Nation Janet Jackson     1

Determine how many songs in this dataset are specifically from the year 2010.

dbGetQuery(con, " SELECT count(*)   FROM sampledb.billboard WHERE year = 2010")
##   _col0
## 1   373

The sample dataset provides certain song properties of interest that can be analyzed to gauge the impact to the song’s overall popularity. Look at one such property, timesignature, and determine the value that is the most frequent among songs in the database. Timesignature is a measure of the number of beats and the type of note involved.

Running the query directly may result in an error, as shown in the commented lines below. This error is a result of trying to retrieve a large result set over a JDBC connection, which can cause out-of-memory issues at the client level. To address this, reduce the fetch size and run again.

#t<-dbGetQuery(con, " SELECT timesignature FROM sampledb.billboard")
#Note:  Running the preceding query results in the following error: 
#Error in .jcall(rp, "I", "fetch", stride, block): java.sql.SQLException: The requested #fetchSize is more than the allowed value in Athena. Please reduce the fetchSize and try #again. Refer to the Athena documentation for valid fetchSize values.
# Use the dbSendQuery function, reduce the fetch size, and run again
r <- dbSendQuery(con, " SELECT timesignature     FROM sampledb.billboard")
dftimesignature<- fetch(r, n=-1, block=100)
dbClearResult(r)
## [1] TRUE
table(dftimesignature)
## dftimesignature
##    0    1    3    4    5    7 
##   10  143  503 6787  112   19
nrow(dftimesignature)
## [1] 7574

From the results, observe that 6787 songs have a timesignature of 4.

Next, determine the song with the highest tempo.

dbGetQuery(con, " SELECT songtitle,artistname,tempo   FROM sampledb.billboard WHERE tempo = (SELECT max(tempo) FROM sampledb.billboard) ")
##                   songtitle      artistname   tempo
## 1 Wanna Be Startin' Somethin' Michael Jackson 244.307

Create the training dataset

Your model needs to be trained such that it can learn and make accurate predictions. Split the data into training and test datasets, and create the training dataset first.  This dataset contains all observations from the year 2009 and earlier. You may face the same JDBC connection issue pointed out earlier, so this query uses a fetch size.

#BillboardTrain <- dbGetQuery(con, "SELECT * FROM sampledb.billboard WHERE year <= 2009")
#Running the preceding query results in the following error:-
#Error in .verify.JDBC.result(r, "Unable to retrieve JDBC result set for ", : Unable to retrieve #JDBC result set for SELECT * FROM sampledb.billboard WHERE year <= 2009 (Internal error)
#Follow the same approach as before to address this issue.

r <- dbSendQuery(con, "SELECT * FROM sampledb.billboard WHERE year <= 2009")
BillboardTrain <- fetch(r, n=-1, block=100)
dbClearResult(r)
## [1] TRUE
BillboardTrain[1:2,c(1:3,6:10)]
##   year           songtitle artistname timesignature
## 1 2009 The Awkward Goodbye    Athlete             3
## 2 2009        Rubik's Cube    Athlete             3
##   timesignature_confidence loudness   tempo tempo_confidence
## 1                    0.732   -6.320  89.614   0.652
## 2                    0.906   -9.541 117.742   0.542
nrow(BillboardTrain)
## [1] 7201

Create the test dataset

BillboardTest <- dbGetQuery(con, "SELECT * FROM sampledb.billboard where year = 2010")
BillboardTest[1:2,c(1:3,11:15)]
##   year              songtitle        artistname key
## 1 2010 This Is the House That Doubt Built A Day to Remember  11
## 2 2010        Sticks & Bricks A Day to Remember  10
##   key_confidence    energy pitch timbre_0_min
## 1          0.453 0.9666556 0.024        0.002
## 2          0.469 0.9847095 0.025        0.000
nrow(BillboardTest)
## [1] 373

Convert the training and test datasets into H2O dataframes

train.h2o <- as.h2o(BillboardTrain)
## 
  |                                                                       
  |                                                                 |   0%
  |                                                                       
  |=================================================================| 100%
test.h2o <- as.h2o(BillboardTest)
## 
  |                                                                       
  |                                                                 |   0%
  |                                                                       
  |=================================================================| 100%

Inspect the column names in your H2O dataframes.

colnames(train.h2o)
##  [1] "year"                     "songtitle"               
##  [3] "artistname"               "songid"                  
##  [5] "artistid"                 "timesignature"           
##  [7] "timesignature_confidence" "loudness"                
##  [9] "tempo"                    "tempo_confidence"        
## [11] "key"                      "key_confidence"          
## [13] "energy"                   "pitch"                   
## [15] "timbre_0_min"             "timbre_0_max"            
## [17] "timbre_1_min"             "timbre_1_max"            
## [19] "timbre_2_min"             "timbre_2_max"            
## [21] "timbre_3_min"             "timbre_3_max"            
## [23] "timbre_4_min"             "timbre_4_max"            
## [25] "timbre_5_min"             "timbre_5_max"            
## [27] "timbre_6_min"             "timbre_6_max"            
## [29] "timbre_7_min"             "timbre_7_max"            
## [31] "timbre_8_min"             "timbre_8_max"            
## [33] "timbre_9_min"             "timbre_9_max"            
## [35] "timbre_10_min"            "timbre_10_max"           
## [37] "timbre_11_min"            "timbre_11_max"           
## [39] "top10"

Create models

You need to designate the independent and dependent variables prior to applying your modeling algorithms. Because you’re trying to predict the ‘top10’ field, this would be your dependent variable and everything else would be independent.

Create your first model using GLM. Because GLM works best with numeric data, you create your model by dropping non-numeric variables. You only use the variables in the dataset that describe the numerical attributes of the song in the logistic regression model. You won’t use these variables:  “year”, “songtitle”, “artistname”, “songid”, or “artistid”.

y.dep <- 39
x.indep <- c(6:38)
x.indep
##  [1]  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
## [24] 29 30 31 32 33 34 35 36 37 38

Create Model 1: All numeric variables

Create Model 1 with the training dataset, using GLM as the modeling algorithm and H2O’s built-in h2o.glm function.

modelh1 <- h2o.glm( y = y.dep, x = x.indep, training_frame = train.h2o, family = "binomial")
## 
  |                                                                       
  |                                                                 |   0%
  |                                                                       
  |=====                                                            |   8%
  |                                                                       
  |=================================================================| 100%

Measure the performance of Model 1, using H2O’s built-in performance function.

h2o.performance(model=modelh1,newdata=test.h2o)
## H2OBinomialMetrics: glm
## 
## MSE:  0.09924684
## RMSE:  0.3150347
## LogLoss:  0.3220267
## Mean Per-Class Error:  0.2380168
## AUC:  0.8431394
## Gini:  0.6862787
## R^2:  0.254663
## Null Deviance:  326.0801
## Residual Deviance:  240.2319
## AIC:  308.2319
## 
## Confusion Matrix (vertical: actual; across: predicted) for F1-optimal threshold:
##          0   1    Error     Rate
## 0      255  59 0.187898  =59/314
## 1       17  42 0.288136   =17/59
## Totals 272 101 0.203753  =76/373
## 
## Maximum Metrics: Maximum metrics at their respective thresholds
##                         metric threshold    value idx
## 1                       max f1  0.192772 0.525000 100
## 2                       max f2  0.124912 0.650510 155
## 3                 max f0point5  0.416258 0.612903  23
## 4                 max accuracy  0.416258 0.879357  23
## 5                max precision  0.813396 1.000000   0
## 6                   max recall  0.037579 1.000000 282
## 7              max specificity  0.813396 1.000000   0
## 8             max absolute_mcc  0.416258 0.455251  23
## 9   max min_per_class_accuracy  0.161402 0.738854 125
## 10 max mean_per_class_accuracy  0.124912 0.765006 155
## 
## Gains/Lift Table: Extract with `h2o.gainsLift(<model>, <data>)` or ` 
h2o.auc(h2o.performance(modelh1,test.h2o)) 
## [1] 0.8431394

The AUC metric provides insight into how well the classifier is able to separate the two classes. In this case, the value of 0.8431394 indicates that the classification is good. (A value of 0.5 indicates a worthless test, while a value of 1.0 indicates a perfect test.)

Next, inspect the coefficients of the variables in the dataset.

dfmodelh1 <- as.data.frame(h2o.varimp(modelh1))
dfmodelh1
##                       names coefficients sign
## 1              timbre_0_max  1.290938663  NEG
## 2                  loudness  1.262941934  POS
## 3                     pitch  0.616995941  NEG
## 4              timbre_1_min  0.422323735  POS
## 5              timbre_6_min  0.349016024  NEG
## 6                    energy  0.348092062  NEG
## 7             timbre_11_min  0.307331997  NEG
## 8              timbre_3_max  0.302225619  NEG
## 9             timbre_11_max  0.243632060  POS
## 10             timbre_4_min  0.224233951  POS
## 11             timbre_4_max  0.204134342  POS
## 12             timbre_5_min  0.199149324  NEG
## 13             timbre_0_min  0.195147119  POS
## 14 timesignature_confidence  0.179973904  POS
## 15         tempo_confidence  0.144242598  POS
## 16            timbre_10_max  0.137644568  POS
## 17             timbre_7_min  0.126995955  NEG
## 18            timbre_10_min  0.123851179  POS
## 19             timbre_7_max  0.100031481  NEG
## 20             timbre_2_min  0.096127636  NEG
## 21           key_confidence  0.083115820  POS
## 22             timbre_6_max  0.073712419  POS
## 23            timesignature  0.067241917  POS
## 24             timbre_8_min  0.061301881  POS
## 25             timbre_8_max  0.060041698  POS
## 26                      key  0.056158445  POS
## 27             timbre_3_min  0.050825116  POS
## 28             timbre_9_max  0.033733561  POS
## 29             timbre_2_max  0.030939072  POS
## 30             timbre_9_min  0.020708113  POS
## 31             timbre_1_max  0.014228818  NEG
## 32                    tempo  0.008199861  POS
## 33             timbre_5_max  0.004837870  POS
## 34                                    NA <NA>

Typically, songs with heavier instrumentation tend to be louder (have higher values in the variable “loudness”) and more energetic (have higher values in the variable “energy”). This knowledge is helpful for interpreting the modeling results.

You can make the following observations from the results:

  • The coefficient estimates for the confidence values associated with the time signature, key, and tempo variables are positive. This suggests that higher confidence leads to a higher predicted probability of a Top 10 hit.
  • The coefficient estimate for loudness is positive, meaning that mainstream listeners prefer louder songs with heavier instrumentation.
  • The coefficient estimate for energy is negative, meaning that mainstream listeners prefer songs that are less energetic, which are those songs with light instrumentation.

These coefficients lead to contradictory conclusions for Model 1. This could be due to multicollinearity issues. Inspect the correlation between the variables “loudness” and “energy” in the training set.

cor(train.h2o$loudness,train.h2o$energy)
## [1] 0.7399067

This number indicates that these two variables are highly correlated, and Model 1 does indeed suffer from multicollinearity. Typically, you associate a value of -1.0 to -0.5 or 1.0 to 0.5 to indicate strong correlation, and a value of 0.1 to 0.1 to indicate weak correlation. To avoid this correlation issue, omit one of these two variables and re-create the models.

You build two variations of the original model:

  • Model 2, in which you keep “energy” and omit “loudness”
  • Model 3, in which you keep “loudness” and omit “energy”

You compare these two models and choose the model with a better fit for this use case.

Create Model 2: Keep energy and omit loudness

colnames(train.h2o)
##  [1] "year"                     "songtitle"               
##  [3] "artistname"               "songid"                  
##  [5] "artistid"                 "timesignature"           
##  [7] "timesignature_confidence" "loudness"                
##  [9] "tempo"                    "tempo_confidence"        
## [11] "key"                      "key_confidence"          
## [13] "energy"                   "pitch"                   
## [15] "timbre_0_min"             "timbre_0_max"            
## [17] "timbre_1_min"             "timbre_1_max"            
## [19] "timbre_2_min"             "timbre_2_max"            
## [21] "timbre_3_min"             "timbre_3_max"            
## [23] "timbre_4_min"             "timbre_4_max"            
## [25] "timbre_5_min"             "timbre_5_max"            
## [27] "timbre_6_min"             "timbre_6_max"            
## [29] "timbre_7_min"             "timbre_7_max"            
## [31] "timbre_8_min"             "timbre_8_max"            
## [33] "timbre_9_min"             "timbre_9_max"            
## [35] "timbre_10_min"            "timbre_10_max"           
## [37] "timbre_11_min"            "timbre_11_max"           
## [39] "top10"
y.dep <- 39
x.indep <- c(6:7,9:38)
x.indep
##  [1]  6  7  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
## [24] 30 31 32 33 34 35 36 37 38
modelh2 <- h2o.glm( y = y.dep, x = x.indep, training_frame = train.h2o, family = "binomial")
## 
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Measure the performance of Model 2.

h2o.performance(model=modelh2,newdata=test.h2o)
## H2OBinomialMetrics: glm
## 
## MSE:  0.09922606
## RMSE:  0.3150017
## LogLoss:  0.3228213
## Mean Per-Class Error:  0.2490554
## AUC:  0.8431933
## Gini:  0.6863867
## R^2:  0.2548191
## Null Deviance:  326.0801
## Residual Deviance:  240.8247
## AIC:  306.8247
## 
## Confusion Matrix (vertical: actual; across: predicted) for F1-optimal threshold:
##          0  1    Error     Rate
## 0      280 34 0.108280  =34/314
## 1       23 36 0.389831   =23/59
## Totals 303 70 0.152815  =57/373
## 
## Maximum Metrics: Maximum metrics at their respective thresholds
##                         metric threshold    value idx
## 1                       max f1  0.254391 0.558140  69
## 2                       max f2  0.113031 0.647208 157
## 3                 max f0point5  0.413999 0.596026  22
## 4                 max accuracy  0.446250 0.876676  18
## 5                max precision  0.811739 1.000000   0
## 6                   max recall  0.037682 1.000000 283
## 7              max specificity  0.811739 1.000000   0
## 8             max absolute_mcc  0.254391 0.469060  69
## 9   max min_per_class_accuracy  0.141051 0.716561 131
## 10 max mean_per_class_accuracy  0.113031 0.761821 157
## 
## Gains/Lift Table: Extract with `h2o.gainsLift(<model>, <data>)` or `h2o.gainsLift(<model>, valid=<T/F>, xval=<T/F>)`
dfmodelh2 <- as.data.frame(h2o.varimp(modelh2))
dfmodelh2
##                       names coefficients sign
## 1                     pitch  0.700331511  NEG
## 2              timbre_1_min  0.510270513  POS
## 3              timbre_0_max  0.402059546  NEG
## 4              timbre_6_min  0.333316236  NEG
## 5             timbre_11_min  0.331647383  NEG
## 6              timbre_3_max  0.252425901  NEG
## 7             timbre_11_max  0.227500308  POS
## 8              timbre_4_max  0.210663865  POS
## 9              timbre_0_min  0.208516163  POS
## 10             timbre_5_min  0.202748055  NEG
## 11             timbre_4_min  0.197246582  POS
## 12            timbre_10_max  0.172729619  POS
## 13         tempo_confidence  0.167523934  POS
## 14 timesignature_confidence  0.167398830  POS
## 15             timbre_7_min  0.142450727  NEG
## 16             timbre_8_max  0.093377516  POS
## 17            timbre_10_min  0.090333426  POS
## 18            timesignature  0.085851625  POS
## 19             timbre_7_max  0.083948442  NEG
## 20           key_confidence  0.079657073  POS
## 21             timbre_6_max  0.076426046  POS
## 22             timbre_2_min  0.071957831  NEG
## 23             timbre_9_max  0.071393189  POS
## 24             timbre_8_min  0.070225578  POS
## 25                      key  0.061394702  POS
## 26             timbre_3_min  0.048384697  POS
## 27             timbre_1_max  0.044721121  NEG
## 28                   energy  0.039698433  POS
## 29             timbre_5_max  0.039469064  POS
## 30             timbre_2_max  0.018461133  POS
## 31                    tempo  0.013279926  POS
## 32             timbre_9_min  0.005282143  NEG
## 33                                    NA <NA>

h2o.auc(h2o.performance(modelh2,test.h2o)) 
## [1] 0.8431933

You can make the following observations:

  • The AUC metric is 0.8431933.
  • Inspecting the coefficient of the variable energy, Model 2 suggests that songs with high energy levels tend to be more popular. This is as per expectation.
  • As H2O orders variables by significance, the variable energy is not significant in this model.

You can conclude that Model 2 is not ideal for this use , as energy is not significant.

CreateModel 3: Keep loudness but omit energy

colnames(train.h2o)
##  [1] "year"                     "songtitle"               
##  [3] "artistname"               "songid"                  
##  [5] "artistid"                 "timesignature"           
##  [7] "timesignature_confidence" "loudness"                
##  [9] "tempo"                    "tempo_confidence"        
## [11] "key"                      "key_confidence"          
## [13] "energy"                   "pitch"                   
## [15] "timbre_0_min"             "timbre_0_max"            
## [17] "timbre_1_min"             "timbre_1_max"            
## [19] "timbre_2_min"             "timbre_2_max"            
## [21] "timbre_3_min"             "timbre_3_max"            
## [23] "timbre_4_min"             "timbre_4_max"            
## [25] "timbre_5_min"             "timbre_5_max"            
## [27] "timbre_6_min"             "timbre_6_max"            
## [29] "timbre_7_min"             "timbre_7_max"            
## [31] "timbre_8_min"             "timbre_8_max"            
## [33] "timbre_9_min"             "timbre_9_max"            
## [35] "timbre_10_min"            "timbre_10_max"           
## [37] "timbre_11_min"            "timbre_11_max"           
## [39] "top10"
y.dep <- 39
x.indep <- c(6:12,14:38)
x.indep
##  [1]  6  7  8  9 10 11 12 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
## [24] 30 31 32 33 34 35 36 37 38
modelh3 <- h2o.glm( y = y.dep, x = x.indep, training_frame = train.h2o, family = "binomial")
## 
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perfh3<-h2o.performance(model=modelh3,newdata=test.h2o)
perfh3
## H2OBinomialMetrics: glm
## 
## MSE:  0.0978859
## RMSE:  0.3128672
## LogLoss:  0.3178367
## Mean Per-Class Error:  0.264925
## AUC:  0.8492389
## Gini:  0.6984778
## R^2:  0.2648836
## Null Deviance:  326.0801
## Residual Deviance:  237.1062
## AIC:  303.1062
## 
## Confusion Matrix (vertical: actual; across: predicted) for F1-optimal threshold:
##          0  1    Error     Rate
## 0      286 28 0.089172  =28/314
## 1       26 33 0.440678   =26/59
## Totals 312 61 0.144772  =54/373
## 
## Maximum Metrics: Maximum metrics at their respective thresholds
##                         metric threshold    value idx
## 1                       max f1  0.273799 0.550000  60
## 2                       max f2  0.125503 0.663265 155
## 3                 max f0point5  0.435479 0.628931  24
## 4                 max accuracy  0.435479 0.882038  24
## 5                max precision  0.821606 1.000000   0
## 6                   max recall  0.038328 1.000000 280
## 7              max specificity  0.821606 1.000000   0
## 8             max absolute_mcc  0.435479 0.471426  24
## 9   max min_per_class_accuracy  0.173693 0.745763 120
## 10 max mean_per_class_accuracy  0.125503 0.775073 155
## 
## Gains/Lift Table: Extract with `h2o.gainsLift(<model>, <data>)` or `h2o.gainsLift(<model>, valid=<T/F>, xval=<T/F>)`
dfmodelh3 <- as.data.frame(h2o.varimp(modelh3))
dfmodelh3
##                       names coefficients sign
## 1              timbre_0_max 1.216621e+00  NEG
## 2                  loudness 9.780973e-01  POS
## 3                     pitch 7.249788e-01  NEG
## 4              timbre_1_min 3.891197e-01  POS
## 5              timbre_6_min 3.689193e-01  NEG
## 6             timbre_11_min 3.086673e-01  NEG
## 7              timbre_3_max 3.025593e-01  NEG
## 8             timbre_11_max 2.459081e-01  POS
## 9              timbre_4_min 2.379749e-01  POS
## 10             timbre_4_max 2.157627e-01  POS
## 11             timbre_0_min 1.859531e-01  POS
## 12             timbre_5_min 1.846128e-01  NEG
## 13 timesignature_confidence 1.729658e-01  POS
## 14             timbre_7_min 1.431871e-01  NEG
## 15            timbre_10_max 1.366703e-01  POS
## 16            timbre_10_min 1.215954e-01  POS
## 17         tempo_confidence 1.183698e-01  POS
## 18             timbre_2_min 1.019149e-01  NEG
## 19           key_confidence 9.109701e-02  POS
## 20             timbre_7_max 8.987908e-02  NEG
## 21             timbre_6_max 6.935132e-02  POS
## 22             timbre_8_max 6.878241e-02  POS
## 23            timesignature 6.120105e-02  POS
## 24                      key 5.814805e-02  POS
## 25             timbre_8_min 5.759228e-02  POS
## 26             timbre_1_max 2.930285e-02  NEG
## 27             timbre_9_max 2.843755e-02  POS
## 28             timbre_3_min 2.380245e-02  POS
## 29             timbre_2_max 1.917035e-02  POS
## 30             timbre_5_max 1.715813e-02  POS
## 31                    tempo 1.364418e-02  NEG
## 32             timbre_9_min 8.463143e-05  NEG
## 33                                    NA <NA>
h2o.sensitivity(perfh3,0.5)
## Warning in h2o.find_row_by_threshold(object, t): Could not find exact
## threshold: 0.5 for this set of metrics; using closest threshold found:
## 0.501855569251422. Run `h2o.predict` and apply your desired threshold on a
## probability column.
## [[1]]
## [1] 0.2033898
h2o.auc(perfh3)
## [1] 0.8492389

You can make the following observations:

  • The AUC metric is 0.8492389.
  • From the confusion matrix, the model correctly predicts that 33 songs will be top 10 hits (true positives). However, it has 26 false positives (songs that the model predicted would be Top 10 hits, but ended up not being Top 10 hits).
  • Loudness has a positive coefficient estimate, meaning that this model predicts that songs with heavier instrumentation tend to be more popular. This is the same conclusion from Model 2.
  • Loudness is significant in this model.

Overall, Model 3 predicts a higher number of top 10 hits with an accuracy rate that is acceptable. To choose the best fit for production runs, record labels should consider the following factors:

  • Desired model accuracy at a given threshold
  • Number of correct predictions for top10 hits
  • Tolerable number of false positives or false negatives

Next, make predictions using Model 3 on the test dataset.

predict.regh <- h2o.predict(modelh3, test.h2o)
## 
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print(predict.regh)
##   predict        p0          p1
## 1       0 0.9654739 0.034526052
## 2       0 0.9654748 0.034525236
## 3       0 0.9635547 0.036445318
## 4       0 0.9343579 0.065642149
## 5       0 0.9978334 0.002166601
## 6       0 0.9779949 0.022005078
## 
## [373 rows x 3 columns]
predict.regh$predict
##   predict
## 1       0
## 2       0
## 3       0
## 4       0
## 5       0
## 6       0
## 
## [373 rows x 1 column]
dpr<-as.data.frame(predict.regh)
#Rename the predicted column 
colnames(dpr)[colnames(dpr) == 'predict'] <- 'predict_top10'
table(dpr$predict_top10)
## 
##   0   1 
## 312  61

The first set of output results specifies the probabilities associated with each predicted observation.  For example, observation 1 is 96.54739% likely to not be a Top 10 hit, and 3.4526052% likely to be a Top 10 hit (predict=1 indicates Top 10 hit and predict=0 indicates not a Top 10 hit).  The second set of results list the actual predictions made.  From the third set of results, this model predicts that 61 songs will be top 10 hits.

Compute the baseline accuracy, by assuming that the baseline predicts the most frequent outcome, which is that most songs are not Top 10 hits.

table(BillboardTest$top10)
## 
##   0   1 
## 314  59

Now observe that the baseline model would get 314 observations correct, and 59 wrong, for an accuracy of 314/(314+59) = 0.8418231.

It seems that Model 3, with an accuracy of 0.8552, provides you with a small improvement over the baseline model. But is this model useful for record labels?

View the two models from an investment perspective:

  • A production company is interested in investing in songs that are more likely to make it to the Top 10. The company’s objective is to minimize the risk of financial losses attributed to investing in songs that end up unpopular.
  • How many songs does Model 3 correctly predict as a Top 10 hit in 2010? Looking at the confusion matrix, you see that it predicts 33 top 10 hits correctly at an optimal threshold, which is more than half the number
  • It will be more useful to the record label if you can provide the production company with a list of songs that are highly likely to end up in the Top 10.
  • The baseline model is not useful, as it simply does not label any song as a hit.

Considering the three models built so far, you can conclude that Model 3 proves to be the best investment choice for the record label.

GBM model

H2O provides you with the ability to explore other learning models, such as GBM and deep learning. Explore building a model using the GBM technique, using the built-in h2o.gbm function.

Before you do this, you need to convert the target variable to a factor for multinomial classification techniques.

train.h2o$top10=as.factor(train.h2o$top10)
gbm.modelh <- h2o.gbm(y=y.dep, x=x.indep, training_frame = train.h2o, ntrees = 500, max_depth = 4, learn_rate = 0.01, seed = 1122,distribution="multinomial")
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perf.gbmh<-h2o.performance(gbm.modelh,test.h2o)
perf.gbmh
## H2OBinomialMetrics: gbm
## 
## MSE:  0.09860778
## RMSE:  0.3140188
## LogLoss:  0.3206876
## Mean Per-Class Error:  0.2120263
## AUC:  0.8630573
## Gini:  0.7261146
## 
## Confusion Matrix (vertical: actual; across: predicted) for F1-optimal threshold:
##          0  1    Error     Rate
## 0      266 48 0.152866  =48/314
## 1       16 43 0.271186   =16/59
## Totals 282 91 0.171582  =64/373
## 
## Maximum Metrics: Maximum metrics at their respective thresholds
##                       metric threshold    value idx
## 1                     max f1  0.189757 0.573333  90
## 2                     max f2  0.130895 0.693717 145
## 3               max f0point5  0.327346 0.598802  26
## 4               max accuracy  0.442757 0.876676  14
## 5              max precision  0.802184 1.000000   0
## 6                 max recall  0.049990 1.000000 284
## 7            max specificity  0.802184 1.000000   0
## 8           max absolute_mcc  0.169135 0.496486 104
## 9 max min_per_class_accuracy  0.169135 0.796610 104
## 10 max mean_per_class_accuracy  0.169135 0.805948 104
## 
## Gains/Lift Table: Extract with `h2o.gainsLift(<model>, <data>)` or `
h2o.sensitivity(perf.gbmh,0.5)
## Warning in h2o.find_row_by_threshold(object, t): Could not find exact
## threshold: 0.5 for this set of metrics; using closest threshold found:
## 0.501205344484314. Run `h2o.predict` and apply your desired threshold on a
## probability column.
## [[1]]
## [1] 0.1355932
h2o.auc(perf.gbmh)
## [1] 0.8630573

This model correctly predicts 43 top 10 hits, which is 10 more than the number predicted by Model 3. Moreover, the AUC metric is higher than the one obtained from Model 3.

As seen above, H2O’s API provides the ability to obtain key statistical measures required to analyze the models easily, using several built-in functions. The record label can experiment with different parameters to arrive at the model that predicts the maximum number of Top 10 hits at the desired level of accuracy and threshold.

H2O also allows you to experiment with deep learning models. Deep learning models have the ability to learn features implicitly, but can be more expensive computationally.

Now, create a deep learning model with the h2o.deeplearning function, using the same training and test datasets created before. The time taken to run this model depends on the type of EC2 instance chosen for this purpose.  For models that require more computation, consider using accelerated computing instances such as the P2 instance type.

system.time(
  dlearning.modelh <- h2o.deeplearning(y = y.dep,
                                      x = x.indep,
                                      training_frame = train.h2o,
                                      epoch = 250,
                                      hidden = c(250,250),
                                      activation = "Rectifier",
                                      seed = 1122,
                                      distribution="multinomial"
  )
)
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##    user  system elapsed 
##   1.216   0.020 166.508
perf.dl<-h2o.performance(model=dlearning.modelh,newdata=test.h2o)
perf.dl
## H2OBinomialMetrics: deeplearning
## 
## MSE:  0.1678359
## RMSE:  0.4096778
## LogLoss:  1.86509
## Mean Per-Class Error:  0.3433013
## AUC:  0.7568822
## Gini:  0.5137644
## 
## Confusion Matrix (vertical: actual; across: predicted) for F1-optimal threshold:
##          0  1    Error     Rate
## 0      290 24 0.076433  =24/314
## 1       36 23 0.610169   =36/59
## Totals 326 47 0.160858  =60/373
## 
## Maximum Metrics: Maximum metrics at their respective thresholds
##                       metric threshold    value idx
## 1                     max f1  0.826267 0.433962  46
## 2                     max f2  0.000000 0.588235 239
## 3               max f0point5  0.999929 0.511811  16
## 4               max accuracy  0.999999 0.865952  10
## 5              max precision  1.000000 1.000000   0
## 6                 max recall  0.000000 1.000000 326
## 7            max specificity  1.000000 1.000000   0
## 8           max absolute_mcc  0.999929 0.363219  16
## 9 max min_per_class_accuracy  0.000004 0.662420 145
## 10 max mean_per_class_accuracy  0.000000 0.685334 224
## 
## Gains/Lift Table: Extract with `h2o.gainsLift(<model>, <data>)` or `h2o.gainsLift(<model>, valid=<T/F>, xval=<T/F>)`
h2o.sensitivity(perf.dl,0.5)
## Warning in h2o.find_row_by_threshold(object, t): Could not find exact
## threshold: 0.5 for this set of metrics; using closest threshold found:
## 0.496293348880151. Run `h2o.predict` and apply your desired threshold on a
## probability column.
## [[1]]
## [1] 0.3898305
h2o.auc(perf.dl)
## [1] 0.7568822

The AUC metric for this model is 0.7568822, which is less than what you got from the earlier models. I recommend further experimentation using different hyper parameters, such as the learning rate, epoch or the number of hidden layers.

H2O’s built-in functions provide many key statistical measures that can help measure model performance. Here are some of these key terms.

Metric Description
Sensitivity Measures the proportion of positives that have been correctly identified. It is also called the true positive rate, or recall.
Specificity Measures the proportion of negatives that have been correctly identified. It is also called the true negative rate.
Threshold Cutoff point that maximizes specificity and sensitivity. While the model may not provide the highest prediction at this point, it would not be biased towards positives or negatives.
Precision The fraction of the documents retrieved that are relevant to the information needed, for example, how many of the positively classified are relevant
AUC

Provides insight into how well the classifier is able to separate the two classes. The implicit goal is to deal with situations where the sample distribution is highly skewed, with a tendency to overfit to a single class.

0.90 – 1 = excellent (A)

0.8 – 0.9 = good (B)

0.7 – 0.8 = fair (C)

.6 – 0.7 = poor (D)

0.5 – 0.5 = fail (F)

Here’s a summary of the metrics generated from H2O’s built-in functions for the three models that produced useful results.

Metric Model 3 GBM Model Deep Learning Model

Accuracy

(max)

0.882038

(t=0.435479)

0.876676

(t=0.442757)

0.865952

(t=0.999999)

Precision

(max)

1.0

(t=0.821606)

1.0

(t=0802184)

1.0

(t=1.0)

Recall

(max)

1.0 1.0

1.0

(t=0)

Specificity

(max)

1.0 1.0

1.0

(t=1)

Sensitivity

 

0.2033898 0.1355932

0.3898305

(t=0.5)

AUC 0.8492389 0.8630573 0.756882

Note: ‘t’ denotes threshold.

Your options at this point could be narrowed down to Model 3 and the GBM model, based on the AUC and accuracy metrics observed earlier.  If the slightly lower accuracy of the GBM model is deemed acceptable, the record label can choose to go to production with the GBM model, as it can predict a higher number of Top 10 hits.  The AUC metric for the GBM model is also higher than that of Model 3.

Record labels can experiment with different learning techniques and parameters before arriving at a model that proves to be the best fit for their business. Because deep learning models can be computationally expensive, record labels can choose more powerful EC2 instances on AWS to run their experiments faster.

Conclusion

In this post, I showed how the popular music industry can use analytics to predict the type of songs that make the Top 10 Billboard charts. By running H2O’s scalable machine learning platform on AWS, data scientists can easily experiment with multiple modeling techniques and interactively query the data using Amazon Athena, without having to manage the underlying infrastructure. This helps record labels make critical decisions on the type of artists and songs to promote in a timely fashion, thereby increasing sales and revenue.

If you have questions or suggestions, please comment below.


Additional Reading

Learn how to build and explore a simple geospita simple GEOINT application using SparkR.


About the Authors

gopalGopal Wunnava is a Partner Solution Architect with the AWS GSI Team. He works with partners and customers on big data engagements, and is passionate about building analytical solutions that drive business capabilities and decision making. In his spare time, he loves all things sports and movies related and is fond of old classics like Asterix, Obelix comics and Hitchcock movies.

 

 

Bob Strahan, a Senior Consultant with AWS Professional Services, contributed to this post.

 

 

Technology to Out Sex Workers

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/10/technology_to_o.html

Two related stories:

PornHub is using machine learning algorithms to identify actors in different videos, so as to better index them. People are worried that it can really identify them, by linking their stage names to their real names.

Facebook somehow managed to link a sex worker’s clients under her fake name to her real profile.

Sometimes people have legitimate reasons for having two identities. That is becoming harder and harder.

Introducing Gluon: a new library for machine learning from AWS and Microsoft

Post Syndicated from Ana Visneski original https://aws.amazon.com/blogs/aws/introducing-gluon-a-new-library-for-machine-learning-from-aws-and-microsoft/

Post by Dr. Matt Wood

Today, AWS and Microsoft announced Gluon, a new open source deep learning interface which allows developers to more easily and quickly build machine learning models, without compromising performance.

Gluon Logo

Gluon provides a clear, concise API for defining machine learning models using a collection of pre-built, optimized neural network components. Developers who are new to machine learning will find this interface more familiar to traditional code, since machine learning models can be defined and manipulated just like any other data structure. More seasoned data scientists and researchers will value the ability to build prototypes quickly and utilize dynamic neural network graphs for entirely new model architectures, all without sacrificing training speed.

Gluon is available in Apache MXNet today, a forthcoming Microsoft Cognitive Toolkit release, and in more frameworks over time.

Neural Networks vs Developers
Machine learning with neural networks (including ‘deep learning’) has three main components: data for training; a neural network model, and an algorithm which trains the neural network. You can think of the neural network in a similar way to a directed graph; it has a series of inputs (which represent the data), which connect to a series of outputs (the prediction), through a series of connected layers and weights. During training, the algorithm adjusts the weights in the network based on the error in the network output. This is the process by which the network learns; it is a memory and compute intensive process which can take days.

Deep learning frameworks such as Caffe2, Cognitive Toolkit, TensorFlow, and Apache MXNet are, in part, an answer to the question ‘how can we speed this process up? Just like query optimizers in databases, the more a training engine knows about the network and the algorithm, the more optimizations it can make to the training process (for example, it can infer what needs to be re-computed on the graph based on what else has changed, and skip the unaffected weights to speed things up). These frameworks also provide parallelization to distribute the computation process, and reduce the overall training time.

However, in order to achieve these optimizations, most frameworks require the developer to do some extra work: specifically, by providing a formal definition of the network graph, up-front, and then ‘freezing’ the graph, and just adjusting the weights.

The network definition, which can be large and complex with millions of connections, usually has to be constructed by hand. Not only are deep learning networks unwieldy, but they can be difficult to debug and it’s hard to re-use the code between projects.

The result of this complexity can be difficult for beginners and is a time-consuming task for more experienced researchers. At AWS, we’ve been experimenting with some ideas in MXNet around new, flexible, more approachable ways to define and train neural networks. Microsoft is also a contributor to the open source MXNet project, and were interested in some of these same ideas. Based on this, we got talking, and found we had a similar vision: to use these techniques to reduce the complexity of machine learning, making it accessible to more developers.

Enter Gluon: dynamic graphs, rapid iteration, scalable training
Gluon introduces four key innovations.

  1. Friendly API: Gluon networks can be defined using a simple, clear, concise code – this is easier for developers to learn, and much easier to understand than some of the more arcane and formal ways of defining networks and their associated weighted scoring functions.
  2. Dynamic networks: the network definition in Gluon is dynamic: it can bend and flex just like any other data structure. This is in contrast to the more common, formal, symbolic definition of a network which the deep learning framework has to effectively carve into stone in order to be able to effectively optimizing computation during training. Dynamic networks are easier to manage, and with Gluon, developers can easily ‘hybridize’ between these fast symbolic representations and the more friendly, dynamic ‘imperative’ definitions of the network and algorithms.
  3. The algorithm can define the network: the model and the training algorithm are brought much closer together. Instead of separate definitions, the algorithm can adjust the network dynamically during definition and training. Not only does this mean that developers can use standard programming loops, and conditionals to create these networks, but researchers can now define even more sophisticated algorithms and models which were not possible before. They are all easier to create, change, and debug.
  4. High performance operators for training: which makes it possible to have a friendly, concise API and dynamic graphs, without sacrificing training speed. This is a huge step forward in machine learning. Some frameworks bring a friendly API or dynamic graphs to deep learning, but these previous methods all incur a cost in terms of training speed. As with other areas of software, abstraction can slow down computation since it needs to be negotiated and interpreted at run time. Gluon can efficiently blend together a concise API with the formal definition under the hood, without the developer having to know about the specific details or to accommodate the compiler optimizations manually.

The team here at AWS, and our collaborators at Microsoft, couldn’t be more excited to bring these improvements to developers through Gluon. We’re already seeing quite a bit of excitement from developers and researchers alike.

Getting started with Gluon
Gluon is available today in Apache MXNet, with support coming for the Microsoft Cognitive Toolkit in a future release. We’re also publishing the front-end interface and the low-level API specifications so it can be included in other frameworks in the fullness of time.

You can get started with Gluon today. Fire up the AWS Deep Learning AMI with a single click and jump into one of 50 fully worked, notebook examples. If you’re a contributor to a machine learning framework, check out the interface specs on GitHub.

-Dr. Matt Wood

Backing Up WordPress

Post Syndicated from Roderick Bauer original https://www.backblaze.com/blog/backing-up-wordpress/

WordPress cloud backup
WordPress logo

WordPress is the most popular CMS (Content Management System) for websites, with almost 30% of all websites in the world using WordPress. That’s a lot of sites — over 350 million!

In this post we’ll talk about the different approaches to keeping the data on your WordPress website safe.


Stop the Presses! (Or the Internet!)

As we were getting ready to publish this post, we received news from UpdraftPlus, one of the biggest WordPress plugin developers, that they are supporting Backblaze B2 as a storage solution for their backup plugin. They shipped the update (1.13.9) this week. This is great news for Backblaze customers! UpdraftPlus is also offering a 20% discount to Backblaze customers wishing to purchase or upgrade to UpdraftPlus Premium. The complete information is below.

UpdraftPlus joins backup plugin developer XCloner — Backup and Restore in supporting Backblaze B2. A third developer, BlogVault, also announced their intent to support Backblaze B2. Contact your favorite WordPress backup plugin developer and urge them to support Backblaze B2, as well.

Now, back to our post…


Your WordPress website data is on a web server that’s most likely located in a large data center. You might wonder why it is necessary to have a backup of your website if it’s in a data center. Website data can be lost in a number of ways, including mistakes by the website owner (been there), hacking, or even domain ownership dispute (I’ve seen it happen more than once). A website backup also can provide a history of changes you’ve made to the website, which can be useful. As an overall strategy, it’s best to have a backup of any data that you can’t afford to lose for personal or business reasons.

Your web hosting company might provide backup services as part of your hosting plan. If you are using their service, you should know where and how often your data is being backed up. You don’t want to find out too late that your backup plan was not adequate.

Sites on WordPress.com are automatically backed up by VaultPress (Automattic), which also is available for self-hosted WordPress installations. If you don’t want the work or decisions involved in managing the hosting for your WordPress site, WordPress.com will handle it for you. You do, however, give up some customization abilities, such as the option to add plugins of your own choice.

Very large and active websites might consider WordPress VIP by Automattic, or another premium WordPress hosting service such as Pagely.com.

This post is about backing up self-hosted WordPress sites, so we’ll focus on those options.

WordPress Backup

Backup strategies for WordPress can be divided into broad categories depending on 1) what you back up, 2) when you back up, and 3) where the data is backed up.

With server data, such as with a WordPress installation, you should plan to have three copies of the data (the 3-2-1 backup strategy). The first is the active data on the WordPress web server, the second is a backup stored on the web server or downloaded to your local computer, and the third should be in another location, such as the cloud.

We’ll talk about the different approaches to backing up WordPress, but we recommend using a WordPress plugin to handle your backups. A backup plugin can automate the task, optimize your backup storage space, and alert you of problems with your backups or WordPress itself. We’ll cover plugins in more detail, below.

What to Back Up?

The main components of your WordPress installation are:

You should decide which of these elements you wish to back up. The database is the top priority, as it contains all your website posts and pages (exclusive of media). Your current theme is important, as it likely contains customizations you’ve made. Following those in priority are any other files you’ve customized or made changes to.

You can choose to back up the WordPress core installation and plugins, if you wish, but these files can be downloaded again if necessary from the source, so you might not wish to include them. You likely have all the media files you use on your website on your local computer (which should be backed up), so it is your choice whether to back these up from the server as well.

If you wish to be able to recreate your entire website easily in case of data loss or disaster, you might choose to back up everything, though on a large website this could be a lot of data.

Generally, you should 1) prioritize any file that you’ve customized that you can’t afford to lose, and 2) decide whether you need a copy of everything in order to get your site back up quickly. These choices will determine your backup method and the amount of storage you need.

A good backup plugin for WordPress enables you to specify which files you wish to back up, and even to create separate backups and schedules for different backup contents. That’s another good reason to use a plugin for backing up WordPress.

When to Back Up?

You can back up manually at any time by using the Export tool in WordPress. This is handy if you wish to do a quick backup of your site or parts of it. Since it is manual, however, it is not a part of a dependable backup plan that should be done regularly. If you wish to use this tool, go to Tools, Export, and select what you wish to back up. The output will be an XML file that uses the WordPress Extended RSS format, also known as WXR. You can create a WXR file that contains all of the information on your site or just portions of the site, such as posts or pages by selecting: All content, Posts, Pages, or Media.
Note: You can use WordPress’s Export tool for sites hosted on WordPress.com, as well.

Export instruction for WordPress

Many of the backup plugins we’ll be discussing later also let you do a manual backup on demand in addition to regularly scheduled or continuous backups.

Note:  Another use of the WordPress Export tool and the WXR file is to transfer or clone your website to another server. Once you have exported the WXR file from the website you wish to transfer from, you can import the WXR file from the Tools, Import menu on the new WordPress destination site. Be aware that there are file size limits depending on the settings on your web server. See the WordPress Codex entry for more information. To make this job easier, you may wish to use one of a number of WordPress plugins designed specifically for this task.

You also can manually back up the WordPress MySQL database using a number of tools or a plugin. The WordPress Codex has good information on this. All WordPress plugins will handle this for you and do it automatically. They also typically include tools for optimizing the database tables, which is just good housekeeping.

A dependable backup strategy doesn’t rely on manual backups, which means you should consider using one of the many backup plugins available either free or for purchase. We’ll talk more about them below.

Which Format To Back Up In?

In addition to the WordPress WXR format, plugins and server tools will use various file formats and compression algorithms to store and compress your backup. You may get to choose between zip, tar, tar.gz, tar.gz2, and others. See The Most Common Archive File Formats for more information on these formats.

Select a format that you know you can access and unarchive should you need access to your backup. All of these formats are standard and supported across operating systems, though you might need to download a utility to access the file.

Where To Back Up?

Once you have your data in a suitable format for backup, where do you back it up to?

We want to have multiple copies of our active website data, so we’ll choose more than one destination for our backup data. The backup plugins we’ll discuss below enable you to specify one or more possible destinations for your backup. The possible destinations for your backup include:

A backup folder on your web server
A backup folder on your web server is an OK solution if you also have a copy elsewhere. Depending on your hosting plan, the size of your site, and what you include in the backup, you may or may not have sufficient disk space on the web server. Some backup plugins allow you to configure the plugin to keep only a certain number of recent backups and delete older ones, saving you disk space on the server.
Email to you
Because email servers have size limitations, the email option is not the best one to use unless you use it to specifically back up just the database or your main theme files.
FTP, SFTP, SCP, WebDAV
FTP, SFTP, SCP, and WebDAV are all widely-supported protocols for transferring files over the internet and can be used if you have access credentials to another server or supported storage device that is suitable for storing a backup.
Sync service (Dropbox, SugarSync, Google Drive, OneDrive)
A sync service is another possible server storage location though it can be a pricier choice depending on the plan you have and how much you wish to store.
Cloud storage (Backblaze B2, Amazon S3, Google Cloud, Microsoft Azure, Rackspace)
A cloud storage service can be an inexpensive and flexible option with pay-as-you go pricing for storing backups and other data.

A good website backup strategy would be to have multiple backups of your website data: one in a backup folder on your web hosting server, one downloaded to your local computer, and one in the cloud, such as with Backblaze B2.

If I had to choose just one of these, I would choose backing up to the cloud because it is geographically separated from both your local computer and your web host, it uses fault-tolerant and redundant data storage technologies to protect your data, and it is available from anywhere if you need to restore your site.

Backup Plugins for WordPress

Probably the easiest and most common way to implement a solid backup strategy for WordPress is to use one of the many backup plugins available for WordPress. Fortunately, there are a number of good ones and are available free or in “freemium” plans in which you can use the free version and pay for more features and capabilities only if you need them. The premium options can give you more flexibility in configuring backups or have additional options for where you can store the backups.

How to Choose a WordPress Backup Plugin

screenshot of WordPress plugins search

When considering which plugin to use, you should take into account a number of factors in making your choice.

Is the plugin actively maintained and up-to-date? You can determine this from the listing in the WordPress Plugin Repository. You also can look at reviews and support comments to get an idea of user satisfaction and how well issues are resolved.

Does the plugin work with your web hosting provider? Generally, well-supported plugins do, but you might want to check to make sure there are no issues with your hosting provider.

Does it support the cloud service or protocol you wish to use? This can be determined from looking at the listing in the WordPress Plugin Repository or on the developer’s website. Developers often will add support for cloud services or other backup destinations based on user demand, so let the developer know if there is a feature or backup destination you’d like them to add to their plugin.

Other features and options to consider in choosing a backup plugin are:

  • Whether encryption of your backup data is available
  • What are the options for automatically deleting backups from the storage destination?
  • Can you globally exclude files, folders, and specific types of files from the backup?
  • Do the options for scheduling automatic backups meet your needs for frequency?
  • Can you exclude/include specific database tables (a good way to save space in your backup)?

WordPress Backup Plugins Review

Let’s review a few of the top choices for WordPress backup plugins.

UpdraftPlus

UpdraftPlus is one of the most popular backup plugins for WordPress with over one million active installations. It is available in both free and Premium versions.

UpdraftPlus just released support for Backblaze B2 Cloud Storage in their 1.13.9 update on September 25. According to the developer, support for Backblaze B2 was the most frequent request for a new storage option for their plugin. B2 support is available in their Premium plugin and as a stand-alone update to their standard product.

Note: The developers of UpdraftPlus are offering a special 20% discount to Backblaze customers on the purchase of UpdraftPlus Premium by using the coupon code backblaze20. The discount is valid until the end of Friday, October 6th, 2017.

screenshot of Backblaze B2 cloud backup for WordPress in UpdraftPlus

XCloner — Backup and Restore

XCloner — Backup and Restore is a useful open-source plugin with many options for backing up WordPress.

XCloner supports B2 Cloud Storage in their free plugin.

screenshot of XCloner WordPress Backblaze B2 backup settings

BlogVault

BlogVault describes themselves as a “complete WordPress backup solution.” They offer a free trial of their paid WordPress backup subscription service that features real-time backups of changes to your WordPress site, as well as many other features.

BlogVault has announced their intent to support Backblaze B2 Cloud Storage in a future update.

screenshot of BlogValut WordPress Backup settings

BackWPup

BackWPup is a popular and free option for backing up WordPress. It supports a number of options for storing your backup, including the cloud, FTP, email, or on your local computer.

screenshot of BackWPup WordPress backup settings

WPBackItUp

WPBackItUp has been around since 2012 and is highly rated. It has both free and paid versions.

screenshot of WPBackItUp WordPress backup settings

VaultPress

VaultPress is part of Automattic’s well-known WordPress product, JetPack. You will need a JetPack subscription plan to use VaultPress. There are different pricing plans with different sets of features.

screenshot of VaultPress backup settings

Backup by Supsystic

Backup by Supsystic supports a number of options for backup destinations, encryption, and scheduling.

screenshot of Backup by Supsystic backup settings

BackupWordPress

BackUpWordPress is an open-source project on Github that has a popular and active following and many positive reviews.

screenshot of BackupWordPress WordPress backup settings

BackupBuddy

BackupBuddy, from iThemes, is the old-timer of backup plugins, having been around since 2010. iThemes knows a lot about WordPress, as they develop plugins, themes, utilities, and provide training in WordPress.

BackupBuddy’s backup includes all WordPress files, all files in the WordPress Media library, WordPress themes, and plugins. BackupBuddy generates a downloadable zip file of the entire WordPress website. Remote storage destinations also are supported.

screenshot of BackupBuddy settings

WordPress and the Cloud

Do you use WordPress and back up to the cloud? We’d like to hear about it. We’d also like to hear whether you are interested in using B2 Cloud Storage for storing media files served by WordPress. If you are, we’ll write about it in a future post.

In the meantime, keep your eye out for new plugins supporting Backblaze B2, or better yet, urge them to support B2 if they’re not already.

The Best Backup Strategy is the One You Use

There are other approaches and tools for backing up WordPress that you might use. If you have an approach that works for you, we’d love to hear about it in the comments.

The post Backing Up WordPress appeared first on Backblaze Blog | Cloud Storage & Cloud Backup.

ISO Rejects NSA Encryption Algorithms

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/09/iso_rejects_nsa.html

The ISO has decided not to approve two NSA-designed block encryption algorithms: Speck and Simon. It’s because the NSA is not trusted to put security ahead of surveillance:

A number of them voiced their distrust in emails to one another, seen by Reuters, and in written comments that are part of the process. The suspicions stem largely from internal NSA documents disclosed by Snowden that showed the agency had previously plotted to manipulate standards and promote technology it could penetrate. Budget documents, for example, sought funding to “insert vulnerabilities into commercial encryption systems.”

More than a dozen of the experts involved in the approval process for Simon and Speck feared that if the NSA was able to crack the encryption techniques, it would gain a “back door” into coded transmissions, according to the interviews and emails and other documents seen by Reuters.

“I don’t trust the designers,” Israeli delegate Orr Dunkelman, a computer science professor at the University of Haifa, told Reuters, citing Snowden’s papers. “There are quite a lot of people in NSA who think their job is to subvert standards. My job is to secure standards.”

I don’t trust the NSA, either.

Confusing Self-Driving Cars by Altering Road Signs

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/08/confusing_self-.html

Researchers found that they could confuse the road sign detection algorithms of self-driving cars by adding stickers to the signs on the road. They could, for example, cause a car to think that a stop sign is a 45 mph speed limit sign. The changes are subtle, though — look at the photo from the article.

Research paper:

Robust Physical-World Attacks on Machine Learning Models,” by Ivan Evtimov, Kevin Eykholt, Earlence Fernandes, Tadayoshi Kohno, Bo Li, Atul Prakash, Amir Rahmati, and Dawn Song:

Abstract: Deep neural network-based classifiers are known to be vulnerable to adversarial examples that can fool them into misclassifying their input through the addition of small-magnitude perturbations. However, recent studies have demonstrated that such adversarial examples are not very effective in the physical world–they either completely fail to cause misclassification or only work in restricted cases where a relatively complex image is perturbed and printed on paper. In this paper we propose a new attack algorithm–Robust Physical Perturbations (RP2)– that generates perturbations by taking images under different conditions into account. Our algorithm can create spatially-constrained perturbations that mimic vandalism or art to reduce the likelihood of detection by a casual observer. We show that adversarial examples generated by RP2 achieve high success rates under various conditions for real road sign recognition by using an evaluation methodology that captures physical world conditions. We physically realized and evaluated two attacks, one that causes a Stop sign to be misclassified as a Speed Limit sign in 100% of the testing conditions, and one that causes a Right Turn sign to be misclassified as either a Stop or Added Lane sign in 100% of the testing conditions.

Uber Drivers Hacking the System to Cause Surge Pricing

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/08/uber_drivers_ha.html

Interesting story about Uber drivers who have figured out how to game the company’s algorithms to cause surge pricing:

According to the study. drivers manipulate Uber’s algorithm by logging out of the app at the same time, making it think that there is a shortage of cars.

[…]

The study said drivers have been coordinating forced surge pricing, after interviews with drivers in London and New York, and research on online forums such as Uberpeople.net. In a post on the website for drivers, seen by the researchers, one person said: “Guys, stay logged off until surge. Less supply high demand = surge.”

.

Passengers, of course, have long had tricks to avoid surge pricing.

I expect to see more of this sort of thing as algorithms become more prominent in our lives.

Hacking Slot Machines by Reverse-Engineering the Random Number Generators

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/08/hacking_slot_ma.html

Interesting story:

The venture is built on Alex’s talent for reverse engineering the algorithms — known as pseudorandom number generators, or PRNGs — that govern how slot machine games behave. Armed with this knowledge, he can predict when certain games are likeliest to spit out money­insight that he shares with a legion of field agents who do the organization’s grunt work.

These agents roam casinos from Poland to Macau to Peru in search of slots whose PRNGs have been deciphered by Alex. They use phones to record video of a vulnerable machine in action, then transmit the footage to an office in St. Petersburg. There, Alex and his assistants analyze the video to determine when the games’ odds will briefly tilt against the house. They then send timing data to a custom app on an agent’s phone; this data causes the phones to vibrate a split second before the agent should press the “Spin” button. By using these cues to beat slots in multiple casinos, a four-person team can earn more than $250,000 a week.

It’s an interesting article; I have no idea how much of it is true.

The sad part is that the slot-machine vulnerability is so easy to fix. Although the article says that “writing such algorithms requires tremendous mathematical skill,” it’s really only true that designing the algorithms requires that skill. Using any secure encryption algorithm or hash function as a PRNG is trivially easy. And there’s no reason why the system can’t be designed with a real RNG. There is some randomness in the system somewhere, and it can be added into the mix as well. The programmers can use a well-designed algorithm, like my own Fortuna, but even something less well-thought-out is likely to foil this attack.

Landmine-clearing Pi-powered C-Turtle

Post Syndicated from Janina Ander original https://www.raspberrypi.org/blog/landmine-c-turtle/

In an effort to create a robot that can teach itself to navigate different terrains, scientists at Arizona State University have built C-Turtle, a Raspberry Pi-powered autonomous cardboard robot with turtle flippers. This is excellent news for people who live in areas with landmines: C-Turtle is a great alternative to current landmine-clearing robots, since it is much cheaper, and much easier to assemble.

C-Turtle ASU

Photo by Charlie Leight/ASU Now

Why turtle flippers?

As any user of Python will tell you*, turtles are amazing. Moreover, as the evolutionary biologist of the C-Turtle team, Andrew Jansen, will tell you, considering their bulk** turtles move very well on land with the help of their flippers. Consequently, the team tried out prototypes with cardboard flippers imitating the shape of turtle flippers. Then they compared their performance to that of prototypes with rectangular or oval ‘flippers’. And 157 million years of evolution*** won out: the robots with turtle flippers were best at moving forward.

C-Turtle ASU

Field testing with Assistant Professor Heni Ben Amor, one of the C-Turtle team’s leaders (Photo by Charlie Leight/ASU Now)

If it walks like a C-Turtle…

But the scientists didn’t just slap turtle flippers on their robot and then tell it to move like a turtle! Instead, they implemented machine learning algorithms on the Pi Zero that serves as C-Turtle’s brain, and then simply let the robot do its thing. Left to its own devices, it used the reward and punishment mechanisms of its algorithms to learn the most optimal way of propelling itself forward. And lo and behold, C-Turtle taught itself to move just like a live turtle does!

Robotic C-Turtle

This is “Robotic C-Turtle” by ASU Now on Vimeo, the home for high quality videos and the people who love them.

Landmine clearance with C-Turtle

Robots currently used to clear landmines are very expensive, since they are built to withstand multiple mine explosions. Conversely, the total cost of C-Turtle comes to about $70 (~£50) – that’s cheap enough to make it disposable. It is also more easily assembled, it doesn’t need to be remotely controlled, and it can learn to navigate new terrains. All this makes it perfect for clearing minefields.

BBC Click on Twitter

Meet C-Turtle, the landmine detecting robot. VIDEO https://t.co/Kjc6WxRC8I

C-Turtles in space?****

The researchers hope that robots similar to C-Turtle can used for space exploration. They found that the C-Turtle prototypes that had performed very well in the sandpits in their lab didn’t really do as well when they were released in actual desert conditions. By analogy, robots optimized for simulated planetary conditions might not actually perform well on-site. The ASU scientists imagine that C-Turtle materials and a laser cutter for the cardboard body could be carried on board a Mars mission. Then Martian C-Turtle design could be optimized after landing, and the robot could teach itself how best to navigate real Martian terrain.

There are already Raspberry Pis in space – imagine if they actually made it to Mars! Dave would never recover

Congrats to Assistant Professors Heni Ben Amor and Daniel Aukes, and to the rest of the C-Turtle team, on their achievement! We at Pi Towers are proud that our little computer is part of this amazing project.

C-Turtle ASU

Photo by Charlie Leight/ASU Now

* Check out our Turtley amazing resource to find out why!

** At a length of 7ft, leatherback sea turtles can weigh 1,500lb!

*** That’s right: turtles survived the extinction of the dinosaurs!

**** Is anyone else thinking of Great A’Tuin right now? Anyone? Just me? Oh well.

The post Landmine-clearing Pi-powered C-Turtle appeared first on Raspberry Pi.