Data Visualization & Reporting Flashcards

When should you use a line chart instead of a bar chart?

Answer: To show trends over continuous time

Line charts are ideal for showing how a value changes over continuous time.

What is 'data-ink ratio' as described by Edward Tufte?

Answer: The proportion of ink used to display actual data versus decoration

Data-ink ratio measures how much of a chart's ink represents real data versus non-essential decoration.

A stakeholder wants to compare the composition of total sales across five regions over four quarters. Which chart works best?

Answer: Stacked bar chart by quarter

A stacked bar chart by quarter shows both totals and regional composition over time.

What is the main purpose of adding filters to an interactive report?

Answer: To let users focus on specific subsets of data

Filters allow users to narrow the view to relevant subsets of the data.

Which practice improves the storytelling quality of a report?

Answer: Guiding the reader with annotations and a logical flow

Annotations and a logical narrative flow help readers interpret and act on the data.

A dual-axis chart is most useful when you need to:

Answer: Show two measures with different scales together

Dual-axis charts let you plot two measures with different scales on the same chart for comparison.

What does 'small multiples' refer to in data visualization?

Answer: A series of similar charts using the same scale for easy comparison

Small multiples are a grid of similar charts with shared scales, enabling quick comparison across categories.