Final (1)

Question 1

What does StandardScaler do?

Answer 1

Scales features to mean 0 and variance 1.

Question 2

What does RobustScaler do?

Answer 2

Scales features using median and IQR (median = 0, IQR = 1).

Question 3

What does MinMaxScaler do?

Answer 3

Scales features to a range between 0 and 1.

Question 4

What does Normalizer do?

Answer 4

Scales each row to have unit norm (length of 1).

Question 5

When do you use Ordinal Encoding?

Answer 5

For ordered categorical values.

Question 6

When do you use One Hot Encoding?

Answer 6

For nominal (unordered) categorical values.

Question 7

What tool helps apply both encoding and scaling?

Answer 7

ColumnTransformer

Question 8

What is “Bag of Words”?

Answer 8

A method that converts text to numerical data by counting word frequency.

Question 9

What does PCA do?

Answer 9

Reduces the number of features and can also de-noise data.

Question 10

What is linear regression’s number of hyperparameters?

Answer 10

None

Question 11

What does Ridge regression add?

Answer 11

L2 regularization via alpha.

Question 12

What does Lasso regression add?

Answer 12

L1 regularization via alpha, can shrink some coefficients to zero.

Question 13

What does a large alpha mean?

Answer 13

More regularization and simpler models.