Machine Learning 101 – Top 20 AWS and Google Certified Machine Learning Specialty Questions and Answers Dumps

Machine learning is an application of artificial intelligence (AI) that provides systems the ability to automatically learn and improve from experience without being explicitly programmed. Machine learning focuses on the development of computer programs that can access data and use it to learn for themselves.

  • By the end of 2020, 85% of customer interactions will be handled without a human (Call Center, Chatbot, etc…)
  • 61% of marketers say artificial intelligence is the most important aspect of their data strategy.
  • 80% of business and tech leaders say AI already boosts productivity (Robotic Process Automation, Power Automate, etc..)
  • Current AI technology can boost business productivity by up to 40%

Professional Machine Learning Engineer designs, builds, and productionizes ML models to solve business challenges using Google Cloud technologies and knowledge of proven ML models and techniques. The ML Engineer collaborates closely with other job roles to ensure long-term success of models. The ML Engineer should be proficient in all aspects of model architecture, data pipeline interaction, and metrics interpretation. The ML Engineer needs familiarity with application development, infrastructure management, data engineering, and security. Through an understanding of training, retraining, deploying, scheduling, monitoring, and improving models, they design and create scalable solutions for optimal performance.

The AWS Certified Machine Learning – Specialty certification is intended for individuals who perform a development or data science role. It validates a candidate’s ability to design, implement, deploy, and maintain machine learning (ML) solutions for given business problems.

This blog covers Machine Learning 101, Top 20 AWS Certified Machine Learning Specialty Questions and Answers, Top 20 Google Professional Machine Learning Engineer Sample Questions, Machine Learning Quizzes, Machine Learning Q&A, Top 10 Machine Learning Algorithms, Machine Learning Latest Hot News, Machine Learning Demos (Ex: Tensorflow Demos)

Below are the Top 20 AWS Certified Machine Learning Specialty Questions and Answers Dumps.

Top

Question1: A machine learning team has several large CSV datasets in Amazon S3. Historically, models built with the Amazon SageMaker Linear Learner algorithm have taken hours to train on similar-sized datasets. The team’s leaders need to accelerate the training process. What can a machine learning specialist do to address this concern?

A) Use Amazon SageMaker Pipe mode.
B) Use Amazon Machine Learning to train the models.
C) Use Amazon Kinesis to stream the data to Amazon SageMaker.
D) Use AWS Glue to transform the CSV dataset to the JSON format.
ANSWER1:

A

Notes/Hint1:

Amazon SageMaker Pipe mode streams the data directly to the container, which improves the performance of training jobs. (Refer to this link for supporting information.) In Pipe mode, your training job streams data directly from Amazon S3. Streaming can provide faster start times for training jobs and better throughput. With Pipe mode, you also reduce the size of the Amazon EBS volumes for your training instances. B would not apply in this scenario. C is a streaming ingestion solution, but is not applicable in this scenario. D transforms the data structure.

Reference1: Amazon SageMaker

Question 2) A local university wants to track cars in a parking lot to determine which students are parking in the lot. The university is wanting to ingest videos of the cars parking in near-real time, use machine learning to identify license plates, and store that data in an AWS data store. Which solution meets these requirements with the LEAST amount of development effort?

A) Use Amazon Kinesis Data Streams to ingest the video in near-real time, use the Kinesis Data Streams consumer integrated with Amazon Rekognition Video to process the license plate information, and then store results in DynamoDB.

B) Use Amazon Kinesis Video Streams to ingest the videos in near-real time, use the Kinesis Video Streams integration with Amazon Rekognition Video to identify the license plate information, and then store the results in DynamoDB.

C) Use Amazon Kinesis Data Streams to ingest videos in near-real time, call Amazon Rekognition to identify license plate information, and then store results in DynamoDB.

D) Use Amazon Kinesis Firehose to ingest the video in near-real time and outputs results onto S3. Set up a Lambda function that triggers when a new video is PUT onto S3 to send results to Amazon Rekognition to identify license plate information, and then store results in DynamoDB.

Answer 2)

B

Notes/Hint2)

Kinesis Video Streams is used to stream videos in near-real time. Amazon Rekognition Video uses Amazon Kinesis Video Streams to receive and process a video stream. After the videos have been processed by Rekognition we can output the results in DynamoDB.

Reference: Kinesis Video Streams

Question 3) A term frequency–inverse document frequency (tf–idf) matrix using both unigrams and bigrams is built from a text corpus consisting of the following two sentences:

1. Please call the number below.
2. Please do not call us. What are the dimensions of the tf–idf matrix?
A) (2, 16)
B) (2, 8)
C) (2, 10)
D) (8, 10)

ANSWER3:

A

Notes/Hint3:

There are 2 sentences, 8 unique unigrams, and 8 unique bigrams, so the result would be (2,16). The phrases are “Please call the number below” and “Please do not call us.” Each word individually (unigram) is “Please,” “call,” ”the,” ”number,” “below,” “do,” “not,” and “us.” The unique bigrams are “Please call,” “call the,” ”the number,” “number below,” “Please do,” “do not,” “not call,” and “call us.” The tf–idf vectorizer is described at this link.

Reference3:  tf-idf vertorizer

Question 4: A company is setting up a system to manage all of the datasets it stores in Amazon S3. The company would like to automate running transformation jobs on the data and maintaining a catalog of the metadata concerning the datasets. The solution should require the least amount of setup and maintenance. Which solution will allow the company to achieve its goals? 

A) Create an Amazon EMR cluster with Apache Hive installed. Then, create a Hive metastore and a script to run transformation jobs on a schedule.
B) Create an AWS Glue crawler to populate the AWS Glue Data Catalog. Then, author an AWS Glue ETL job, and set up a schedule for data transformation jobs.
C) Create an Amazon EMR cluster with Apache Spark installed. Then, create an Apache Hive metastore and a script to run transformation jobs on a schedule. D) Create an AWS Data Pipeline that transforms the data. Then, create an Apache Hive metastore and a script to run transformation jobs on a schedule.
 

ANSWER4:

B

Notes/Hint4:

AWS Glue is the correct answer because this option requires the least amount of setup and maintenance since it is serverless, and it does not require management of the infrastructure. Refer to this link for supporting information. A, C, and D are all solutions that can solve the problem, but require more steps for configuration, and require higher operational overhead to run and maintain.
Reference4:  Glue

Question 5) Which service in the Kinesis family allows you to easily load streaming data into data stores and analytics tools?

A) Kinesis Firehose
B) Kinesis Streams
C) Kinesis Data Analytics
D) Kinesis Video Streams
 

ANSWER5:

A

Notes/Hint5:

Kinesis Firehose is perfect for streaming data into AWS and sending it directly to its final destination – places like S3, Redshift, Elastisearch, and Splunk Instances.

Reference 5): Kinesis Firehose

Question 6) A data scientist is working on optimizing a model during the training process by varying multiple parameters. The data scientist observes that, during multiple runs with identical parameters, the loss function converges to different, yet stable, values. What should the data scientist do to improve the training process? 
A) Increase the learning rate. Keep the batch size the same.
B) Reduce the batch size. Decrease the learning rate.
C) Keep the batch size the same. Decrease the learning rate.
D) Do not change the learning rate. Increase the batch size.
 
Answer  6)

B
 

Notes 6)

It is most likely that the loss function is very curvy and has multiple local minima where the training is getting stuck. Decreasing the batch size would help the data scientist stochastically get out of the local minima saddles. Decreasing the learning rate would prevent overshooting the global loss function minimum. Refer to the paper at this link for an explanation.
Reference 6) : Here

Question 7) Your organization has a standalone Javascript (Node.js) application that streams data into AWS using Kinesis Data Streams. You notice that they are using the Kinesis API (AWS SDK) over the Kinesis Producer Library (KPL). What might be the reasoning behind this?
A) The Kinesis API (AWS SDK) provides greater functionality over the Kinesis Producer Library.
B) The Kinesis API (AWS SDK) runs faster in Javascript applications over the Kinesis Producer Library.
C) The Kinesis Producer Library must be installed as a Java application to use with Kinesis Data Streams.
D) The Kinesis Producer Library cannot be integrated with a Javascript application because of its asynchronous architecture.
Answer 7)

C
Notes/Hint7:

The KPL must be installed as a Java application before it can be used with your Kinesis Data Streams. There are ways to process KPL serialized data within AWS Lambda, in Java, Node.js, and Python, but not if these answers mentions Lambda.
Reference 7) KPL
 
 
Question 8) A data scientist is evaluating different binary classification models. A false positive result is 5 times more expensive (from a business perspective) than a false negative result. The models should be evaluated based on the following criteria: 
1) Must have a recall rate of at least 80%
2) Must have a false positive rate of 10% or less
3) Must minimize business costs After creating each binary classification model, the data scientist generates the corresponding confusion matrix. Which confusion matrix represents the model that satisfies the requirements?
A) TN = 91, FP = 9 FN = 22, TP = 78
 B) TN = 99, FP = 1 FN = 21, TP = 79
C) TN = 96, FP = 4 FN = 10, TP = 90
D) TN = 98, FP = 2 FN = 18, TP = 82
 
Answer 8): 

D
 

Notes/Hint 8)


The following calculations are required: TP = True Positive FP = False Positive FN = False Negative TN = True Negative FN = False Negative Recall = TP / (TP + FN) False Positive Rate (FPR) = FP / (FP + TN) Cost = 5 * FP + FN A B C D Recall 78 / (78 + 22) = 0.78 79 / (79 + 21) = 0.79 90 / (90 + 10) = 0.9 82 / (82 + 18) = 0.82 False Positive Rate 9 / (9 + 91) = 0.09 1 / (1 + 99) = 0.01 4 / (4 + 96) = 0.04 2 / (2 + 98) = 0.02 Costs 5 * 9 + 22 = 67 5 * 1 + 21 = 26 5 * 4 + 10 = 30 5 * 2 + 18 = 28 Options C and D have a recall greater than 80% and an FPR less than 10%, but D is the most cost effective. For supporting information, refer to this link.
Reference 8: Here

 
 
Question 9) A data scientist uses logistic regression to build a fraud detection model. While the model accuracy is 99%, 90% of the fraud cases are not detected by the model. What action will definitely help the model detect more than 10% of fraud cases? 
A) Using undersampling to balance the dataset
B) Decreasing the class probability threshold
C) Using regularization to reduce overfitting
D) Using oversampling to balance the dataset
 

Answer  9)

B

 

Notes 9)

Decreasing the class probability threshold makes the model more sensitive and, therefore, marks more cases as the positive class, which is fraud in this case. This will increase the likelihood of fraud detection. However, it comes at the price of lowering precision. This is covered in the Discussion section of the paper at this link
Reference 9: Here

 
 
Question 10) A company is interested in building a fraud detection model. Currently, the data scientist does not have a sufficient amount of information due to the low number of fraud cases. Which method is MOST likely to detect the GREATEST number of valid fraud cases?
A) Oversampling using bootstrapping
B) Undersampling
C) Oversampling using SMOTE
D) Class weight adjustment
 

Answer  10)

C

 
Notes 10)

With datasets that are not fully populated, the Synthetic Minority Over-sampling Technique (SMOTE) adds new information by adding synthetic data points to the minority class. This technique would be the most effective in this scenario. Refer to Section 4.2 at this link for supporting information.
Reference 10) : Here

 
Question 11) A machine learning engineer is preparing a data frame for a supervised learning task with the Amazon SageMaker Linear Learner algorithm. The ML engineer notices the target label classes are highly imbalanced and multiple feature columns contain missing values. The proportion of missing values across the entire data frame is less than 5%. What should the ML engineer do to minimize bias due to missing values? 
 
A) Replace each missing value by the mean or median across non-missing values in same row.
B) Delete observations that contain missing values because these represent less than 5% of the data.
C) Replace each missing value by the mean or median across non-missing values in the same column.
D) For each feature, approximate the missing values using supervised learning based on other features.
 

Answer  11)

D

 

Notes 11)

Use supervised learning to predict missing values based on the values of other features. Different supervised learning approaches might have different performances, but any properly implemented supervised learning approach should provide the same or better approximation than mean or median approximation, as proposed in responses A and C. Supervised learning applied to the imputation of missing values is an active field of research. Refer to this link for an example.
Reference 11): Here

 
Question 12) A company has collected customer comments on its products, rating them as safe or unsafe, using decision trees. The training dataset has the following features: id, date, full review, full review summary, and a binary safe/unsafe tag. During training, any data sample with missing features was dropped. In a few instances, the test set was found to be missing the full review text field. For this use case, which is the most effective course of action to address test data samples with missing features? 
A) Drop the test samples with missing full review text fields, and then run through the test set.
B) Copy the summary text fields and use them to fill in the missing full review text fields, and then run through the test set.
C) Use an algorithm that handles missing data better than decision trees.
D) Generate synthetic data to fill in the fields that are missing data, and then run through the test set.
 
Answer  12)

B

 

 

Notes 12) 

In this case, a full review summary usually contains the most descriptive phrases of the entire review and is a valid stand-in for the missing full review text field. For supporting information, refer to page 1627 at this link, and this link and this link.

Reference 12) Here

 
Question 13) An insurance company needs to automate claim compliance reviews because human reviews are expensive and error-prone. The company has a large set of claims and a compliance label for each. Each claim consists of a few sentences in English, many of which contain complex related information. Management would like to use Amazon SageMaker built-in algorithms to design a machine learning supervised model that can be trained to read each claim and predict if the claim is compliant or not. Which approach should be used to extract features from the claims to be used as inputs for the downstream supervised task? 
A) Derive a dictionary of tokens from claims in the entire dataset. Apply one-hot encoding to tokens found in each claim of the training set. Send the derived features space as inputs to an Amazon SageMaker builtin supervised learning algorithm.
B) Apply Amazon SageMaker BlazingText in Word2Vec mode to claims in the training set. Send the derived features space as inputs for the downstream supervised task.
C) Apply Amazon SageMaker BlazingText in classification mode to labeled claims in the training set to derive features for the claims that correspond to the compliant and non-compliant labels, respectively.
D) Apply Amazon SageMaker Object2Vec to claims in the training set. Send the derived features space as inputs for the downstream supervised task.
 

Answer  13)

D

 

Notes 13)

Amazon SageMaker Object2Vec generalizes the Word2Vec embedding technique for words to more complex objects, such as sentences and paragraphs. Since the supervised learning task is at the level of whole claims, for which there are labels, and no labels are available at the word level, Object2Vec needs be used instead of Word2Vec.

Reference 13)  Amazon SageMaker
Object2Vec 

Question 14) You have been tasked with capturing two different types of streaming events. The first event type includes mission-critical data that needs to immediately be processed before operations can continue. The second event type includes data of less importance, but operations can continue without immediately processing. What is the most appropriate solution to record these different types of events?

A) Capture both events with the PutRecords API call.
B) Capture both event types using the Kinesis Producer Library (KPL).
C) Capture the mission critical events with the PutRecords API call and the second event type with the Kinesis Producer Library (KPL).
D) Capture the mission critical events with the Kinesis Producer Library (KPL) and the second event type with the Putrecords API call.
 

Answer  14)

C

 

Notes 14)

The question is about sending data to Kinesis synchronously vs. asynchronously. PutRecords is a synchronous send function, so it must be used for the first event type (critical events). The Kinesis Producer Library (KPL) implements an asynchronous send function, so it can be used for the second event type. In this scenario, the reason to use the KPL over the PutRecords API call is because: KPL can incur an additional processing delay of up to RecordMaxBufferedTime within the library (user-configurable). Larger values of RecordMaxBufferedTime results in higher packing efficiencies and better performance. Applications that cannot tolerate this additional delay may need to use the AWS SDK directly. For more information about using the AWS SDK with Kinesis Data Streams, see Developing Producers Using the Amazon Kinesis Data Streams API with the AWS SDK for Java. For more information about RecordMaxBufferedTime and other user-configurable properties of the KPL, see Configuring the Kinesis Producer Library.

Reference 14: KCL vs PutRecords

Question 15) You are collecting clickstream data from an e-commerce website to make near-real time product suggestions for users actively using the site. Which combination of tools can be used to achieve the quickest recommendations and meets all of the requirements?

A) Use Kinesis Data Streams to ingest clickstream data, then use Kinesis Data Analytics to run real time SQL queries to gain actionable insights and trigger real-time recommendations with AWS Lambda functions based on conditions.
B) Use Kinesis Data Firehose to ingest click stream data, then use Kinesis Data Analytics to run real time SQL queries to gain actionable insights and trigger real-time recommendations with AWS Lambda functions based on conditions, then use Lambda to load these results into S3.
C) Use Kinesis Data Streams to ingest clickstream data, then use Lambda to process that data and write it to S3. Once the data is on S3, use Athena to query based on conditions that data and make real time recommendations to users.
D) Use the Kinesis Data Analytics to ingest the clickstream data directly and run real time SQL queries to gain actionable insights and trigger real-time recommendations with AWS Lambda functions based on conditions.
 

Answer  15)

A

 

Notes 15)

Kinesis Data Analytics gets its input streaming data from Kinesis Data Streams or Kinesis Data Firehose. You can use Kinesis Data Analytics to run real-time SQL queries on your data. Once certain conditions are met you can trigger Lambda functions to make real time product suggestions to users. It is not important that we store or persist the clickstream data.

Reference 15: Kinesis Data Analytics

Question 16) Which service built by AWS makes it easy to set up a retry mechanism, aggregate records to improve throughput, and automatically submits CloudWatch metrics?

A) Kinesis API (AWS SDK)
B) Kinesis Producer Library (KPL)
C) Kinesis Consumer Library
D) Kinesis Client Library (KCL)

Answer  16)

B

 

Notes 16)

Although the Kinesis API built into the AWS SDK can be used for all of this, the Kinesis Producer Library (KPL) makes it easy to integrate all of this into your applications.

Reference 16:  Kinesis Producer Library (KPL) 

Question 17) You have been tasked with capturing data from an online gaming platform to run analytics on and process through a machine learning pipeline. The data that you are ingesting is players controller inputs every 1 second (up to 10 players in a game) that is in JSON format. The data needs to be ingested through Kinesis Data Streams and the JSON data blob is 100 KB in size. What is the minimum number of shards you can use to successfully ingest this data?

A) 10 shards
B) Greater than 500 shards, so you’ll need to request more shards from AWS
C) 1 shard
D) 100 shards

Answer  17)

C

 

Notes 17)

In this scenario, there will be a maximum of 10 records per second with a max payload size of 1000 KB (10 records x 100 KB = 1000KB) written to the shard. A single shard can ingest up to 1 MB of data per second, which is enough to ingest the 1000 KB from the streaming game play. Therefor 1 shard is enough to handle the streaming data.

Reference 17: shards

Question 18) Which services in the Kinesis family allows you to analyze streaming data, gain actionable insights, and respond to your business and customer needs in real time?

A) Kinesis Streams
B) Kinesis Firehose
C) Kinesis Video Streams
D) Kinesis Data Analytics

Answer  18)

D

 

Notes 18)

Kinesis Data Analytics allows you to run real-time SQL queries on your data to gain insights and respond to events in real time.

Reference 18: Kinesis Data Analytics

Question 19) You are a ML specialist needing to collect data from Twitter tweets. Your goal is to collect tweets that include only the name of your company and the tweet body, and store it off into a data store in AWS. What set of tools can you use to stream, transform, and load the data into AWS with the LEAST amount of effort?

A) Setup a Kinesis Data Firehose for data ingestion and immediately write that data to S3. Next, setup a Lambda function to trigger when data lands in S3 to transform it and finally write it to DynamoDB.
B) Setup A Kinesis Data Stream for data ingestion, setup EC2 instances as data consumers to poll and transform the data from the stream. Once the data is transformed, make an API call to write the data to DynamoDB.
C) Setup Kinesis Data Streams for data ingestion. Next, setup Kinesis Data Firehouse to load that data into RedShift. Next, setup a Lambda function to query data using RedShift spectrum and store the results onto DynamoDB.
D) Create a Kinesis Data Stream to ingest the data. Next, setup a Kinesis Data Firehose and use Lambda to transform the data from the Kinesis Data Stream, then use Lambda to write the data to DynamoDB. Finally, use S3 as the data destination for Kinesis Data Firehose.
 

Answer 19)

A

Notes 19)

All of these could be used to stream, transform, and load the data into an AWS data store. The setup that requires the LEAST amount of effort and moving parts involves setting up a Kinesis Data Firehose to stream the data into S3, have it transformed by Lambda with an S3 trigger, and then written to DynamoDB.

Reference 19: Kinesis Data Firehose to stream the data into S3

Question 20) Which service in the Kinesis family allows you to build custom applications that process or analyze streaming data for specialized needs?

A) Kinesis Firehose
B) Kinesis Streams
C) Kinesis Video Streams
D) Kinesis Data Analytics

Answer 20)

B

Notes 20)

Kinesis Streams allows you to stream data into AWS and build custom applications around that streaming data.

Reference 20: Kinesis Streams

 

Top

Top 10 Google Professional Machine Learning Engineer Sample Questions

Question 1: You work for a textile manufacturer and have been asked to build a model to detect and classify fabric defects. You trained a machine learning model with high recall based on high resolution images taken at the end of the production line. You want quality control inspectors to gain trust in your model. Which technique should you use to understand the rationale of your classifier?

A. Use K-fold cross validation to understand how the model performs on different test datasets.

B. Use the Integrated Gradients method to efficiently compute feature attributions for each predicted image.

C. Use PCA (Principal Component Analysis) to reduce the original feature set to a smaller set of easily understood features.

D. Use k-means clustering to group similar images together, and calculate the Davies-Bouldin index to evaluate the separation between clusters.

Answer 1)

B

Notes 1)

B is correct because it identifies the pixel of the input image that leads to the classification of the image itself.

Question 2: You need to write a generic test to verify whether Dense Neural Network (DNN) models automatically released by your team have a sufficient number of parameters to learn the task for which they were built. What should you do?

A. Train the model for a few iterations, and check for NaN values.
B. Train the model for a few iterations, and verify that the loss is constant.
C. Train a simple linear model, and determine if the DNN model outperforms it.
D. Train the model with no regularization, and verify that the loss function is close to zero.

 

Answer 2)

D

Notes 2)

D is correct because the test can check that the model has enough parameters to memorize the task.

 

Top

Machine Learning Q&A:

 
 
 

At a high level, these skills are a combination of software and data engineering.

The persons that are more appropriate to do this job are a data engineer and/or a machine learning engineer.

That being said, if you work at a startup or happen to be in a small company and need to put the models into production yourself, here are the top skills you need to get:

  • Well structured code: it doesn’t need to be perfect but at least can be understood and updated by other team members. Avoid spaghetti code[1] as the plague.
  • Add logs: if you are a Python user, the logging[2] module is your friend. Avoid print statements at any cost.
  • Model versioning: add a hash key to your different models. You will thank me later.
  • Metadata everywhere: save as much data about your models and ML experiments as you can (running time, hyperparameters, used features, CV scores, and so on). You will thank me later, again.
  • Monitor performances: execution time and statistical scores of your models.
  • Data and models management: store the necessary data and models somewhere that is available to everyone (S3[3] for example). Avoid uploading these to your VCS[4] system. Don’t share them using Slack or Drive. I won’t judge you though, I do it sometimes (read often). Read more here …..

Some of the mistakes that might involve during building a machine learning model (I can think of) are listed here:

  1. Not understanding the structure of the dataset
  2. Not giving proper care during features selection
  3. Leaving out categorical features and considering just numerical variables
  4. Falling into dummy variable trap
  5. Selection of inefficient machine learning algorithm
  6. Not trying out various ML algorithms for building the model based on structure of data.
  7. Improper tuning of model parameters
  8. Most importantly: Building an idiotstic imperfect model i.e. suppose we have a classification problem with 99% chances of falling into class1 and remaining to class2. The built model may develop a mapping function which all the time for all data inputs, may predict the result to be class1. Well, one might say his/her model has 99% accuracy. But in reality the 1% class2 case hasn’t been included in the model. So this must be taken into consideration.
  9. Read more here…

Basically, data mining is a key aspect of data analytics. Some even consider the former as essential to execute before the latter. While data analytics is the complete package and involves most components needed to examine a data set and extract valuable information, data mining focuses specifically on identifying hidden patterns.

That’s just the surface-level comparison though. The image above gives an overview of how the two differ.

One such difference is the presence of a hypothesis. Data analytics usually requires coming up with one, as it aims to find specific answers. Data mining, on the other hand, generally doesn’t need one to test or prove. The expected output are patterns or trends, which doesn’t require coming up with a statement or fact to test.

However, that doesn’t mean you mine data blindly. You still have a goal, whether it’s to come up with a recommender system or identify predictors of a certain dimension. Ultimately though, you strive to come up with data patterns or trends. For data analysis on the other hand, you’re expected to come up with valuable and actionable insights, usually in relation to a predetermined hypothesis. Read more here ….

The data science life cycle is not something well-defined like the software development life-cycle, and there is no ‘one-size-fits-all’ solution for data science projects. Every step in the life-cycle of a data science project depends on various data scientist skills and data science tools. The typical life-cycle of a data science project involves jumping back and forth among various interdependent science tasks using a variety of tools, techniques, programming, etc.

Thus, the data science life-cycle can include the following steps:

  1. Business requirement understanding.
  2. Data collection.
  3. Data cleaning.
  4. Data analysis.
  5. Modeling.
  6. Performance evaluation.
  7. Communicating with stakeholders.
  8. Deployment.
  9. Real-world testing.
  10. Business buy-in.
  11. Support and maintenance.

Looks neat, but here is the scheme to visualize how it is happening in reality:

Agile development processes, especially continuous delivery lends itself well to the data science project life-cycle. The early comparison helps the data science team to change approaches, refine hypotheses and even discard the project if the business case is nonviable or the benefits from the predictive models are not worth the effort to build it.

Read more here….

 

Top

Machine Learning Latest News

Top

Top 10 Machine Learning Algorithms

Source: Top 10 Machine Learning Algorithms for Data Scientist

In machine learning, there’s something called the “No Free Lunch” theorem. In a nutshell, it states that no one algorithm works best for every problem. It’s especially relevant for supervised learning. For example, you can’t say that neural networks are always better than decision trees or vice-versa. Furthermore, there are many factors at play, such as the size and structure of your dataset. As a result, you should try many different algorithms for your problem!

Top ML Algorithms

1. Linear Regression

Regression is a technique for numerical prediction. Additionally, regression is a statistical measure that attempts to determine the strength of the relationship between two variables. One is a dependent variable. Other is from a series of other changing variables which are our independent variables. Moreover, just like Classification is for predicting categorical labels, Regression is for predicting a continuous value. For example, we may wish to predict the salary of university graduates with 5 years of work experience. We use regression to determine how much specific factors or sectors influence the dependent variable.

Linear regression attempts to model the relationship between a scalar variable and explanatory variables by fitting a linear equation. For example, one might want to relate the weights of individuals to their heights using a linear regression model.

Additionally, this operator calculates a linear regression model. It uses the Akaike criterion for model selection. Furthermore, the Akaike information criterion is a measure of the relative goodness of a fit of a statistical model.

2. Logistic Regression

Logistic regression is a classification model. It uses input variables to predict a categorical outcome variable. The variable can take on one of a limited set of class values. A binomial logistic regression relates to two binary output categories. A multinomial logistic regression allows for more than two classes. Examples of logistic regression include classifying a binary condition as “healthy” / “not healthy”. Logistic regression applies the logistic sigmoid function to weighted input values to generate a prediction of the data class.

A logistic regression model estimates the probability of a dependent variable as a function of independent variables. The dependent variable is the output that we are trying to predict. The independent variables or explanatory variables are the factors that we feel could influence the output. Multiple regression refers to regression analysis with two or more independent variables. Multivariate regression, on the other hand, refers to regression analysis with two or more dependent variables.

3. Linear Discriminant Analysis

Logistic Regression is a classification algorithm traditionally for two-class classification problems. If you have more than two classes then the Linear Discriminant Analysis algorithm is the preferred linear classification technique.

The representation of LDA is pretty straight forward. It consists of statistical properties of your data, calculated for each class. For a single input variable this includes:

  1. The mean value for each class.
  2. The variance calculated across all classes.

We make predictions by calculating a discriminate value for each class. After that we make a prediction for the class with the largest value. The technique assumes that the data has a Gaussian distribution. Hence, it is a good idea to remove outliers from your data beforehand. It’s a simple and powerful method for classification predictive modelling problems.

4. Classification and Regression Trees

Prediction Trees are for predicting response or class YY from input X1, X2,…,XnX1,X2,…,Xn. If it is a continuous response it is a regression tree, if it is categorical, it is a classification tree. At each node of the tree, we check the value of one the input XiXi. Depending on the (binary) answer we continue to the left or to the right subbranch. When we reach a leaf we will find the prediction.

Contrary to linear or polynomial regression which are global models, trees try to partition the data space into small enough parts where we can apply a simple different model on each part. The non-leaf part of the tree is just the procedure to determine for each data xx what is the model we will use to classify it.

5. Naive Bayes

A Naive Bayes Classifier is a supervised machine-learning algorithm that uses the Bayes’ Theorem, which assumes that features are statistically independent. The theorem relies on the naive assumption that input variables are independent of each other, i.e. there is no way to know anything about other variables when given an additional variable. Regardless of this assumption, it has proven itself to be a classifier with good results.

Naive Bayes Classifiers rely on the Bayes’ Theorem, which is based on conditional probability or in simple terms, the likelihood that an event (A) will happen given that another event (B) has already happened. Essentially, the theorem allows a hypothesis to be updated each time new evidence is introduced. The equation below expresses Bayes’ Theorem in the language of probability:

Let’s explain what each of these terms means.

  • “P” is the symbol to denote probability.
  • P(A | B) = The probability of event A (hypothesis) occurring given that B (evidence) has occurred.
  • P(B | A) = The probability of the event B (evidence) occurring given that A (hypothesis) has occurred.
  • P(A) = The probability of event B (hypothesis) occurring.
  • P(B) = The probability of event A (evidence) occurring.

6. K-Nearest Neighbors

k-nearest neighbours (or k-NN for short) is a simple machine learning algorithm that categorizes an input by using its k nearest neighbours.

For example, suppose a k-NN algorithm has an input of data points of specific men and women’s weight and height, as plotted below. To determine the gender of an unknown input (green point), k-NN can look at the nearest k neighbours (suppose ) and will determine that the input’s gender is male. This method is a very simple and logical way of marking unknown inputs, with a high rate of success.

Also, we can k-NN in a variety of machine learning tasks; for example, in computer vision, k-NN can help identify handwritten letters and in gene expression analysis, the algorithm can determine which genes contribute to a certain characteristic. Overall, k-nearest neighbours provide a combination of simplicity and effectiveness that makes it an attractive algorithm to use for many machine learning tasks.

7. Learning Vector Quantization

A downside of K-Nearest Neighbors is that you need to hang on to your entire training dataset. The Learning Vector Quantization algorithm (or LVQ for short) is an artificial neural network algorithm that allows you to choose how many training instances to hang onto and learns exactly what those instances should look like.

Additionally, the representation for LVQ is a collection of codebook vectors. We select them randomly in the beginning and adapted to best summarize the training dataset over a number of iterations of the learning algorithm. After learned, the codebook vectors can make predictions just like K-Nearest Neighbors. Also, we find the most similar neighbour (best matching codebook vector) by calculating the distance between each codebook vector and the new data instance. The class value or (real value in the case of regression) for the best matching unit is then returned as the prediction. Moreover, you can get the best results if you rescale your data to have the same range, such as between 0 and 1.

If you discover that KNN gives good results on your dataset try using LVQ to reduce the memory requirements of storing the entire training dataset.

8. Bagging and Random Forest

A Random Forest consists of a collection or ensemble of simple tree predictors, each capable of producing a response when presented with a set of predictor values. For classification problems, this response takes the form of a class membership, which associates, or classifies, a set of independent predictor values with one of the categories present in the dependent variable. Alternatively, for regression problems, the tree response is an estimate of the dependent variable given the predictors.e

A Random Forest consists of an arbitrary number of simple trees, which determine the final outcome. For classification problems, the ensemble of simple trees votes for the most popular class. In the regression problem, we average responses to obtain an estimate of the dependent variable. Using tree ensembles can lead to significant improvement in prediction accuracy (i.e., better ability to predict new data cases).

9. SVM

A Support Vector Machine (SVM) is a supervised machine learning algorithm that can be employed for both classification and regression purposes. Also, SVMs have more common usage in classification problems and as such, this is what we will focus on in this post.

SVMs are based on the idea of finding a hyperplane that best divides a dataset into two classes, as shown in the image below.

Also, you can think of a hyperplane as a line that linearly separates and classifies a set of data.

Intuitively, the further from the hyperplane our data points lie, the more confident we are that they have been correctly classified. We, therefore, want our data points to be as far away from the hyperplane as possible, while still being on the correct side of it.

So when we add a new testing data , whatever side of the hyperplane it lands will decide the class that we assign to it.

The distance between the hyperplane and the nearest data point from either set is the margin. Furthermore, the goal is to choose a hyperplane with the greatest possible margin between the hyperplane and any point within the training set, giving a greater chance of correct classification of data.

But the data is rarely ever as clean as our simple example above. A dataset will often look more like the jumbled balls below which represent a linearly non-separable dataset.

10. Boosting and AdaBoost

Boosting is an ensemble technique that attempts to create a strong classifier from a number of weak classifiers. We do this by building a model from the training data, then creating a second model that attempts to correct the errors from the first model. We can add models until the training set is predicted perfectly or a maximum number of models are added.

AdaBoost was the first really successful boosting algorithm developed for binary classification. It is the best starting point for understanding boosting. Modern boosting methods build on AdaBoost, most notably stochastic gradient boosting machines.

AdaBoost is used with short decision trees. After the first tree is created, the performance of the tree on each training instance is used to weight how much attention the next tree that is created should pay attention to each training instance. Training data that is hard to predict is given more weight, whereas easy to predict instances are given less weight. Models are created sequentially one after the other, each updating the weights on the training instances that affect the learning performed by the next tree in the sequence. After all the trees are built, predictions are made for new data, and the performance of each tree is weighted by how accurate it was on training data.

Because so much attention is put on correcting mistakes by the algorithm it is important that you have clean data with outliers removed.

Summary

A typical question asked by a beginner, when facing a wide variety of machine learning algorithms, is “which algorithm should I use?” The answer to the question varies depending on many factors, including: (1) The size, quality, and nature of data; (2) The available computational time; (3) The urgency of the task; and (4) What you want to do with the data.

Even an experienced data scientist cannot tell which algorithm will perform the best before trying different algorithms. Although there are many other Machine Learning algorithms, these are the most popular ones. If you’re a newbie to Machine Learning, these would be a good starting point to learn.

Follow this link, if you are looking to learn Data Science Course Online!

Additionally, if you are having an interest in learning Data Science, Learn online Data Science Course to boost your career in Data Science.

Also, learn AWS Big Data Course click here, AWS Online Course

Furthermore, if you want to read more about data science, read this Data Science blogs

Top

The foundations of most algorithms lie in linear algebra, multivariable calculus, and optimization methods. Most algorithms use a sequence of combinations to estimate an objective function given a set of data, and the sequence order and included methods distinguish one algorithm from another. It’s helpful to learn enough math to read the development papers associated with key algorithms in the field, as many other methods (or one’s own innovations) include pieces of those algorithms. It’s like learning the language of machine learning. Once you are fluent in it, it’s pretty easy to modify algorithms as needed and create new ones likely to improve on a problem in a short period of time.

Matrix factorization: a simple, beautiful way to do dimensionality reduction —and dimensionality reduction is the essence of cognition. Recommender systems would be a big application of matrix factorization. Another application I’ve been using over the years (starting in 2010 with video data) is factorizing a matrix of pairwise mutual information (or pointwise mutual information, which is more common) between features, which can be used for feature extraction, computing word embeddings, computing label embeddings (that was the topic of a recent paper of mine [1]), etc.

Used in a convolutional settings, this acts as an excellent unsupervised feature extractor for images and videos. There’s one big issue though: it is fundamentally a shallow algorithm. Deep neural networks will quickly outperform it if any kind of supervision labels are available.

[1] [1607.05691] Information-theoretical label embeddings for large-scale image classification

Machine Learning Demos:

1- TensorFlow Demos

LipSync by YouTube

See how well you synchronize to the lyrics of the popular hit “Dance Monkey.” This in-browser experience uses the Facemesh model for estimating key points around the lips to score lip-syncing accuracy.Explore demo  View code  

Emoji Scavenger Hunt

Use your phone’s camera to identify emojis in the real world. Can you find all the emojis before time expires?Explore demo  View code  

Webcam Controller

Play Pac-Man using images trained in your browser.Explore demo  View code  

Teachable Machine

No coding required! Teach a machine to recognize images and play sounds.Explore demo  View code  

Move Mirror

Explore pictures in a fun new way, just by moving around.Explore demo  View code  

Performance RNN

Enjoy a real-time piano performance by a neural network.Explore demo  View code  

Node.js Pitch Prediction

Train a server-side model to classify baseball pitch types using Node.js.View code  

Visualize Model Training

See how to visualize in-browser training and model behaviour and training using tfjs-vis.Explore demo  View code  

Community demos

Get started with official templates and explore top picks from the community for inspiration.Glitch 

Check out community Glitches and make your own TensorFlow.js-powered projects.Explore Glitch  Codepen 

Fork boilerplate templates and check out working examples from the community.Explore CodePen  GitHub Community Projects 

See what the community has created and submitted to the TensorFlow.js gallery page.Explore GitHub  

https://cdpn.io/jasonmayes/fullcpgrid/QWbNeJdOpen in Editor

Real time body segmentation using TensorFlow.js

Load in a pre-trained Body-Pix model from the TensorFlow.js team so that you can locate all pixels in an image that are part of a body, and what part of the body they belong to. Clone this to make your own TensorFlow.js powered projects to recognize body parts in images from your webcam and more!

New Pen from Templatehttps://cdpn.io/jasonmayes/fullcpgrid/qBEJxggOpen in Editor

Multiple object detection using pre trained model in TensorFlow.js

This demo shows how we can use a pre made machine learning solution to recognize objects (yes, more than one at a time!) on any image you wish to present to it. Even better, not only do we know that the image contains an object, but we can also get the co-ordinates of the bounding box for each object it finds, which allows you to highlight the found object in the image.

For this demo we are loading a model using the ImageNet-SSD architecture, to recognize 90 common objects it has already been taught to find from the COCO dataset.

If what you want to recognize is in that list of things it knows about (for example a cat, dog, etc), this may be useful to you as is in your own projects, or just to experiment with Machine Learning in the browser and get familiar with the possibilities of machine learning.

If you are feeling particularly confident you can check out our GitHub documentation (https://github.com/tensorflow/tfjs-models/tree/master/coco-ssd) which goes into much more detail for customizing various parameters to tailor performance to your needs.

New Pen from Templatehttps://cdpn.io/jasonmayes/fullcpgrid/JjompwwOpen in Editor

Classifying images using a pre trained model in TensorFlow.js

This demo shows how we can use a pre made machine learning solution to classify images (aka a binary image classifier). It should be noted that this model works best when a single item is in the image at a time. Busy images may not work so well. You may want to try our demo for Multiple Object Detection (https://codepen.io/jasonmayes/pen/qBEJxgg) for that.

For this demo we are loading a model using the MobileNet architecture, to recognize 1000 common objects it has already been taught to find from the ImageNet data set (http://image-net.org/).

If what you want to recognize is in that list of things it knows about (for example a cat, dog, etc), this may be useful to you as is in your own projects, or just to experiment with Machine Learning in the browser and get familiar with the possibilities of machine learning.

Please note: This demo loads an easy to use JavaScript class made by the TensorFlow.js team to do the hardwork for you so no machine learning knowledge is needed to use it.

If you were looking to learn how to load in a TensorFlow.js saved model directly yourself then please see our tutorial on loading TensorFlow.js models directly.

If you want to train a system to recognize your own objects, using your own data, then check out our tutorials on “transfer learning”.

New Pen from TemplateOpen in Editor

Tensorflow.js Boilerplate

The hello world for TensorFlow.js 🙂 Absolute minimum needed to import into your website and simply prints the loaded TensorFlow.js version. From here we can do great things. Clone this to make your own TensorFlow.js powered projects or if you are following a tutorial that needs TensorFlow.js to work.

New Pen from Template

Examples

tfjs-examples provides small code examples that implement various ML tasks using TensorFlow.js.MNIST Digit Recognizer

Train a model to recognize handwritten digits from the MNIST database.Explore example  View code  Addition RNN

Train a model to learn addition from text examples.Explore example  View code  

TensorFlow.js Layers: Iris Demo

More TensorFlow examples









taimienphi.vn