Machine Learning with Viya® 3.4® Lesson 2: Data Preparation

Question 1

For a new project that you are creating in SAS Model Studio, you wish to use a SAS data set that is not in memory but exists on your local machine. In which tab would this data set be located?

Answer 1

Data sets that are located on your local machine can be found in Import.

Question 2

For a new project that you are creating in SAS Model Studio, you wish to use a SAS data set that is not in memory but exists on your connected server (not the local machine). In which tab would this data set be located?

Answer 2

All data sets that exist on a connected server are found in Data Sources.

Question 3

What are the four groups of Advanced project settings in Model Studio?

Answer 3

1. Advisor Options
2. Partition Data
3. Event-based Sampling
4. Node Configuration

Question 4

What are the default proportions when data is partitioned for event-based sampling?

Answer 4

• 60% Training
• 30% Validation
• 10% Test

Question 5

Where would you adjust the threshold for rejecting inputs with missing values?

Answer 5

Adjust the maximum percent missing under the Advisor Options group in the Advanced Project Settings

Question 6

What is the validation data that the Variable Selection node creates from the training data used for?

Answer 6

Model assessment during the modeling process

Question 7

The Data Exploration node enables you to do what?

Answer 7

View the most Important inputs or Screening to see suspicious variables.

Question 8

What is the best practice for handling high-cardinality input variables?

Answer 8

binning

Question 9

Which Model Studio setting determines whether a numeric input is designated as interval or nominal?

Answer 9

If a numeric input has more distinct values/levels than the interval cutoff value, it is declared interval. Otherwise, it is declared nominal.

Question 10

Where would you specify the interval cut-off in Model Studio?

Answer 10

In the Advisor Options group under Advanced Project settings

Question 11

How would you define variable metadata and assign rules to modify variables?

Answer 11

You can perform these tasks using either the Data tab or the Manage Variables node.

Question 12

What does the temporary table produced in a Save Data node following a Decision Tree contain?

Answer 12

Following a decision tree, the table contains predicted probabilities and leaf IDs

Question 13

What can you do using the Manage Variables node after a pipeline is run?

Answer 13

Set up imputation and transformation rules.

Question 14

What does the Manage Variables node enable you to do in Model Studio?

Answer 14

modify the data such as changing the role of a variable or adding transformations to the data within a pipeline, turn on event-based sampling before a pipeline is run

Question 15

Which variable selection technique identifies the set of input variables that jointly explain the maximum amount of variance contained in the data when using the Variable Selection node in Model Studio?

Answer 15

Unsupervised Selection

Question 16

What does the Text Mining node do?

Answer 16

Creates topics based on groups of terms that occur together in several documents

Question 17

What is the purpose of the Feature Extraction node in Model Studio?

Answer 17

the Feature Extraction node transforms the existing features (variables) into a lower-dimensional space by generating new features that are composites of the original features

Question 18

What is the drawback to Feature Extraction?

Answer 18

Composite variables are no longer meaningful with respect to the original problem

Question 19

What is another term for a feature in predictive modeling?

Answer 19

Input

Question 20

How would you specify the threshold for rejecting categorical variables in Model Studio?

Answer 20

Set the maximum class levels under the Advisor Options group in Advanced Project settings

Question 21

Where can you set up imputation and transformation rules in Model Studio?

Answer 21

In the Manage Variables node after a pipeline is run

Question 22

For a new project that you are creating in SAS Model Studio, you wish to use a SAS data set loaded into memory. In which tab would this data set be located?

Answer 22

CAS tables loaded into memory are seen in Available.

Question 23

Does the Variable Selection node use supervised methods or unsupervised methods to select inputs?

Answer 23

The Variable Selection node can perform input selection based on both supervised and unsupervised methods.

Question 24

What is the curse of dimensionality?

Answer 24

The more inputs you use to build the model, the more cases are required to discover the relationship between the inputs and the target

Question 25

Why it is important to reduce the number of inputs during data preparation?

Answer 25

The more inputs you use to build the model, the more cases are required to discover the relationship between the inputs and the target

Question 26

What does the Save Data node do?

Answer 26

The Save Data node produces a temporary table in a CAS library.

Question 27

What does the Replacement node enable you to do?

Answer 27

replace outliers and unknown class values with specified values

Question 28

How do the transformations available in the Transformations node minimize bias in model predictions?

Answer 28

by reducing the effect of extreme or unusual input values

Question 29

What are some of the techniques used in the Feature Extraction node in Model Studio?

Answer 29

principal component analysis (PCA), robust PCA, singular value decomposition (SVD), and autoencoders

Question 30

What is binning?

Answer 30

Binning is a method of transformation that converts numeric inputs to categories or groups the levels of a high-cardinality input.

Question 31

Which transformation creates bins for a numeric variable?

Answer 31

A quantile transformation creates bins for a numeric variable.

Question 32

What would you use the Anomaly Detection node in Model Studio for?

Answer 32

the Anomaly Detection node is used to identify and exclude anomalies using the support vector data description (SVDD)

Question 33

When would it be helpful to use the Anonamly Detection node?

Answer 33

when using a data set where most of the data belongs to one class and the other class is scarce or missing

Question 34

What does the Filtering node do?

Answer 34

The Filtering node excludes certain observations such as rare or extreme values

Question 35

Assume the Target has an event proportion of 2% in the original data. You want to build models where event-based sampling has been used such that the modeling data set will have a 50% event proportion. What are the two ways this can be done using Model Studio?

Answer 35

1. While the project is being created, after the data source has been selected, click the Advanced button. Select the Event-Based Sampling option. Turn on event-based sampling by checking the check box.
2. After the project is created but before a pipeline has been run, go into project settings, select the Event-Based Sampling option. Turn on event-based sampling by checking the check box.

Question 36

What are some reasons for performing transformations on your data?

Answer 36

stabilizing variances,

removing non-linearity,

and correcting non-normality

Question 37

What is the default maximum cardinality for determining whether or not to reject a nominal variable?

Answer 37

20

Question 38

Is the Maximum percent missing option is turned on by default?

Answer 38

Yes

Question 39

What is Singular Value Decomposition (SVD)?

Answer 39

Singular value decomposition(SVD) projects the high-dimensional document and term spaces into a lower dimension space.

Question 40

What is SVD used for when selecting model inputs?

Answer 40

The singular values can be thought of as providing a measure of importance used to decide how many dimensions to keep.

Question 41

What does the Transformation node enable you to do?

Answer 41

alter your data by replacing an input variable with some function of that variable