DSE Exploratory Data Analysis Techniques 2

Question 1

Which statistical measure is most resistant to the influence of outliers?

Accepted Answer

Median

Answer

The median is resistant to outliers because it depends only on the middle value(s) of the sorted data, not the magnitude of extreme values.

Question 2

A violin plot combines features of which two visualizations?

Accepted Answer

Box plot and kernel density estimate

Answer

A violin plot shows a box plot inside a mirrored kernel density estimate, providing both summary statistics and the full distribution shape.

Question 3

When exploring a dataset with 50 variables, which technique is most useful for quickly identifying correlated pairs?

Accepted Answer

Correlation heatmap

Answer

A correlation heatmap color-encodes all pairwise correlations in a compact grid, making patterns across many variables immediately visible.

Question 4

What does a Q-Q (quantile-quantile) plot primarily assess?

Accepted Answer

Whether a dataset follows a theoretical distribution

Answer

A Q-Q plot compares the quantiles of observed data against the quantiles of a theoretical distribution; points near the diagonal line indicate a good fit.

Question 5

Which of the following best describes 'data binning' in EDA?

Accepted Answer

Grouping continuous values into discrete intervals

Answer

Binning converts continuous variables into discrete categories (bins) to simplify analysis and reduce noise.

DSE - Data Science Practice Test

DSE - Data Science Practice Test

DSE Exploratory Data Analysis Techniques 2