dell d-ds-fn-23 practice test

In time series analysis, what statement describes a MA(q) process?

• A. Current deviation from the time series mean depends on the q previous deviations
• B. Current deviation from the time series mean depends on the quotient q
• C. Current time series value depends on the q previous values
• D. Current time series value depends on the fitted polynomial of order q

After running a density plot you realize that the data has a long tail to the right. What can you do to
make the dataset more normally distributed?

• A. Use a scatter plot to obtain a better picture
• B. Use a histogram to obtain a better picture
• C. Apply a square transformation
• D. Apply a logarithmic transformation

Which R function plots a distribution of a single variable along two different axes?

• A. table()
• B. summaryQ
• C. density ()
• D. rug()

What action occurs during feature selection in the model building phase of the data analytics
lifecycle?

• A. Create new combinations of attributes
• B. Overfit the model to improve prediction accuracy
• C. Identify the most useful input variables
• D. Select a superset of variables to shorten training times

Which Hadoop service responds to requests for compute and memory resources?

• A. Application Manager
• B. DataNode
• C. Scheduler
• D. Application Master

What converts SQL-like commands into either Tez, Spark, or MapReduce jobs that are submitted to
the Hadoop cluster?

• A. Pig
• B. HBase
• C. Hive
• D. Mahout

What is the similarity between the matrix and array data structures in R?

• A. Both structures can contain only integers
• B. Both structures can only contain one data type
• C. Both structures can store multiple data types
• D. Both structures must be 2-dimensional

Which visualization technique should be avoided?

• A. Using a small number of contrasting colors to draw distinctions
• B. Using tables of numbers to present all of the data visually
• C. Achieving a high data-ink ratio
• D. Using visuals to illustrate key points

Which analytic technique would be appropriate to estimate home sale price in U.S. dollars as a
function of square footage, number of bedrooms, and lot size?

• A. Time series analysis
• B. Linear regression
• C. Naive Bayesian classification
• D. K-means clustering

How should project results be communicated to executives and the project sponsor?

• A. Focus on business outcomes and benefits
• B. Demonstrate your technical prowess to establish credibility
• C. Provide model performance visualizations
• D. Emphasize coding details and technical requirements