Data Science Data Visualization and Communication 3

Question 1

Which chart is best for showing a trend in a continuous metric over time?

Accepted Answer

Line chart

Answer

Line charts connect ordered time points to clearly show trends and direction over time.

Question 2

A stakeholder says your dashboard is 'too busy.' Which action most directly addresses this?

Accepted Answer

Reduce clutter and highlight only the most relevant metrics

Answer

Simplifying and focusing on key metrics reduces cognitive load and improves clarity.

Question 3

Which encoding is generally perceived most accurately by the human eye (per Cleveland & McGill)?

Accepted Answer

Position along a common scale

Answer

Position along a common scale is the most accurately perceived visual encoding for quantitative values.

Question 4

What is the primary risk of using a dual-axis chart with two different y-scales?

Accepted Answer

It can imply spurious correlation by arbitrary scaling

Answer

Independent scaling of two axes can make unrelated series appear correlated, misleading viewers.

Question 5

Which visualization best displays the magnitude of values across two categorical dimensions simultaneously?

Accepted Answer

Heatmap

Answer

A heatmap uses color intensity in a grid to show values across two categorical axes.

Data Science Practice Test