Data Visualization Statistical Visualization 1

Question 1

What does a correlation matrix heatmap visualize?

Accepted Answer

Pairwise correlation coefficients between multiple variables using color intensity

Answer

A correlation matrix heatmap displays the correlation coefficients between all pairs of variables using color intensity to indicate strength and direction of relationships.

Question 2

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

Accepted Answer

Whether a dataset follows a specific theoretical distribution, typically normal

Answer

A Q-Q plot compares the quantiles of sample data against the quantiles of a theoretical distribution; points falling on a straight line indicate the data follows that distribution.

Question 3

What statistical information does a violin plot add compared to a box plot?

Accepted Answer

The full probability density distribution shape of the data

Answer

Violin plots add a kernel density estimate to the box plot structure, showing the full shape of the data distribution including bimodality and skewness.

Question 4

What is a 'kernel density estimate' (KDE) plot used for?

Accepted Answer

Visualizing the probability density function of a continuous variable using a smooth curve

Answer

KDE plots smooth out histogram bars into a continuous curve representing the estimated probability density function of the underlying data.

Question 5

What does a control chart (Shewhart chart) display that a regular line chart does not?

Accepted Answer

Upper and lower control limits based on statistical variation to detect process instability

Answer

Control charts add statistically derived upper and lower control limits (UCL/LCL) to a time series, allowing identification of points that indicate process variation beyond normal chance.

Data Visualization Practice Test

Data Visualization Practice Test

Data Visualization Statistical Visualization 1