4

Practice Set 4

Questions 31–40 (10 questions)

31

A monitoring service generates 1 TB of scale metrics record data every minute. A Research team performs queries on this data using Amazon Athena. The queries run slowly due to the large volume of data, and the team requires better performance.How should the records be stored in Amazon S3 to improve query performance? [{"voted_answers": "B", "vote_count": 8, "is_most_voted": true}]

32

Machine Learning Specialist is working with a media company to perform classification on popular articles from the company's website. The company is using random forests to classify how popular an article will be before it is published. A sample of the data being used is below.Given the dataset, the Specialist wants to convert the Day_Of_Week column to binary values.What technique should be used to convert this column to binary values? [{"voted_answers": "B", "vote_count": 3, "is_most_voted": true}]

33

A gaming company has launched an online game where people can start playing for free, but they need to pay if they choose to use certain features. The company needs to build an automated system to predict whether or not a new user will become a paid user within 1 year. The company has gathered a labeled dataset from 1 million users.The training dataset consists of 1,000 positive samples (from users who ended up paying within 1 year) and 999,000 negative samples (from users who did not use any paid features). Each data sample consists of 200 features including user age, device, location, and play patterns.Using this dataset for training, the Data Science team trained a random forest model that converged with over 99% accuracy on the training set. However, the prediction results on a test dataset were not satisfactoryWhich of the following approaches should the Data Science team take to mitigate this issue? (Choose two.) [{"voted_answers": "CD", "vote_count": 7, "is_most_voted": true}]

34

A Data Scientist is developing a machine learning model to predict future patient outcomes based on information collected about each patient and their treatment plans. The model should output a continuous value as its prediction. The data available includes labeled outcomes for a set of 4,000 patients. The study was conducted on a group of individuals over the age of 65 who have a particular disease that is known to worsen with age.Initial models have performed poorly. While reviewing the underlying data, the Data Scientist notices that, out of 4,000 patient observations, there are 450 where the patient age has been input as 0. The other features for these observations appear normal compared to the rest of the sample populationHow should the Data Scientist correct this issue? [{"voted_answers": "B", "vote_count": 22, "is_most_voted": true}, {"voted_answers": "D", "vote_count": 6, "is_most_voted": false}]

35

A Data Science team is designing a dataset repository where it will store a large amount of training data commonly used in its machine learning models. As DataScientists may create an arbitrary number of new datasets every day, the solution has to scale automatically and be cost-effective. Also, it must be possible to explore the data using SQL.Which storage scheme is MOST adapted to this scenario? [{"voted_answers": "A", "vote_count": 6, "is_most_voted": true}]

36

A Machine Learning Specialist deployed a model that provides product recommendations on a company's website. Initially, the model was performing very well and resulted in customers buying more products on average. However, within the past few months, the Specialist has noticed that the effect of product recommendations has diminished and customers are starting to return to their original habits of spending less. The Specialist is unsure of what happened, as the model has not changed from its initial deployment over a year ago.Which method should the Specialist try to improve model performance? [{"voted_answers": "D", "vote_count": 4, "is_most_voted": true}]

37

A Machine Learning Specialist working for an online fashion company wants to build a data ingestion solution for the company's Amazon S3-based data lake.The Specialist wants to create a set of ingestion mechanisms that will enable future capabilities comprised of:✑ Real-time analytics✑ Interactive analytics of historical data✑ Clickstream analytics✑ Product recommendationsWhich services should the Specialist use? [{"voted_answers": "A", "vote_count": 9, "is_most_voted": true}]

38

A company is observing low accuracy while training on the default built-in image classification algorithm in Amazon SageMaker. The Data Science team wants to use an Inception neural network architecture instead of a ResNet architecture.Which of the following will accomplish this? (Choose two.) [{"voted_answers": "CD", "vote_count": 6, "is_most_voted": true}]

39

A Machine Learning Specialist built an image classification deep learning model. However, the Specialist ran into an overfitting problem in which the training and testing accuracies were 99% and 75%, respectively.How should the Specialist address this issue and what is the reason behind it? [{"voted_answers": "B", "vote_count": 19, "is_most_voted": true}]

40

A Machine Learning team uses Amazon SageMaker to train an Apache MXNet handwritten digit classifier model using a research dataset. The team wants to receive a notification when the model is overfitting. Auditors want to view the Amazon SageMaker log activity report to ensure there are no unauthorized API calls.What should the Machine Learning team do to address the requirements with the least amount of code and fewest steps? [{"voted_answers": "B", "vote_count": 7, "is_most_voted": true}, {"voted_answers": "D", "vote_count": 1, "is_most_voted": false}]