Data Science Data Science-DATA Science 1

Question 1

Which measure of central tendency is most resistant to the influence of outliers?

Accepted Answer

Median

Answer

Mean

Answer

Mode

Answer

Standard deviation

Question 2

What is the primary purpose of cross-validation in machine learning?

Accepted Answer

To assess how well a model generalizes to unseen data

Answer

To speed up model training

Answer

To increase the size of the training dataset

Answer

To remove outliers from the dataset

Question 3

In a neural network, what is the role of the activation function?

Accepted Answer

To introduce non-linearity into the model

Answer

To initialize the weights of the network

Answer

To normalize the input features

Answer

To calculate the loss between predictions and labels

Question 4

Which SQL clause is used to filter rows after a GROUP BY aggregation has been applied?

Accepted Answer

HAVING

Answer

WHERE

Answer

FILTER

Answer

CASE

Question 5

What does a confusion matrix's 'precision' metric measure?

Accepted Answer

The proportion of predicted positives that are truly positive

Answer

The proportion of actual positives correctly identified

Answer

The total accuracy across all classes

Answer

The ratio of false negatives to true positives

Question 6

Which data transformation technique scales features so they have a mean of 0 and a standard deviation of 1?

Accepted Answer

Standardization (Z-score scaling)

Answer

Min-Max normalization

Answer

Log transformation

Answer

Binarization