Quiz: Visualization Gallery

Q: How many chart types does the gallery contain? A) 25 B) 35 C) 50 D) 100

C. 50 chart types across 9 categories.

Q: Which category includes bar charts, lollipop charts, and slope charts? A) Composition B) Comparison C) Distribution D) Trend

B. Comparison — chart types for "which is bigger/smaller/different."

Q: Which chart type is best for showing how a value builds up through additions and subtractions? A) Waterfall B) Funnel C) Sankey D) Treemap

A. Waterfall charts show how a starting value is modified by successive additions and subtractions to reach a final value.

Q: Which gallery category includes histograms, KDEs, and violin plots? A) Relationship B) Trend C) Distribution D) Comparison

C. Distribution — chart types for "how is a variable spread out."

Q: When should you use a lollipop chart instead of a standard bar chart? A) When data is temporal B) When there are many categories and bars would be visually heavy C) When showing proportions D) When data is geographic

B. Lollipop charts (thin stem + dot) are visually lighter than bars, making them better for ranked lists with many items.

Q: Which chart type shows two values per item connected by a line, typically for before/after comparisons? A) Slope chart B) Dumbbell chart C) Connected scatter D) Parallel coordinates

B. Dumbbell charts show two dots connected by a line for each item, comparing two states (before/after, 2020/2024, actual/target).

Q: Which chart type uses 100 small squares to show a percentage? A) Pie B) Donut C) Waffle D) Treemap

C. Waffle charts display a 10x10 grid of squares with filled squares representing the percentage. More engaging than pie for some audiences.

Q: Which Plotly trace type is used for financial OHLC data? A) `go.Scatter` B) `go.Candlestick` C) `go.Bar` D) `go.Waterfall`

B. `go.Candlestick` renders financial open-high-low-close data with traditional candlestick markers.

Q: The gallery's quick-reference decision table maps: A) Libraries to chart types B) Colors to chart types C) Question types to best chart types D) Datasets to chart types

C. The decision table maps question types ("what are the parts of the whole?", "how does X change over time?") to the best chart type options and alternatives.

Q: Which gallery category is described as "controversial" because its chart types are often misused? A) Composition (pie charts) B) Specialized (radar charts) C) Both A and B D) Neither

C. Both pie charts (often misused for too many categories) and radar charts (often misused for data better shown as bars) come with usage warnings in the gallery.

Quiz: Visualization Gallery

Part I: Multiple Choice (10 questions)

Q1. How many chart types does the gallery contain?

A) 25 B) 35 C) 50 D) 100

Answer

**C.** 50 chart types across 9 categories.

Q2. Which category includes bar charts, lollipop charts, and slope charts?

A) Composition B) Comparison C) Distribution D) Trend

Answer

**B.** Comparison — chart types for "which is bigger/smaller/different."

Q3. Which chart type is best for showing how a value builds up through additions and subtractions?

A) Waterfall B) Funnel C) Sankey D) Treemap

Answer

**A.** Waterfall charts show how a starting value is modified by successive additions and subtractions to reach a final value.

Q4. Which gallery category includes histograms, KDEs, and violin plots?

A) Relationship B) Trend C) Distribution D) Comparison

Answer

**C.** Distribution — chart types for "how is a variable spread out."

Q5. When should you use a lollipop chart instead of a standard bar chart?

A) When data is temporal B) When there are many categories and bars would be visually heavy C) When showing proportions D) When data is geographic

Answer

**B.** Lollipop charts (thin stem + dot) are visually lighter than bars, making them better for ranked lists with many items.

Q6. Which chart type shows two values per item connected by a line, typically for before/after comparisons?

A) Slope chart B) Dumbbell chart C) Connected scatter D) Parallel coordinates

Answer

**B.** Dumbbell charts show two dots connected by a line for each item, comparing two states (before/after, 2020/2024, actual/target).

Q7. Which chart type uses 100 small squares to show a percentage?

A) Pie B) Donut C) Waffle D) Treemap

Answer

**C.** Waffle charts display a 10x10 grid of squares with filled squares representing the percentage. More engaging than pie for some audiences.

Q8. Which Plotly trace type is used for financial OHLC data?

A) go.Scatter B) go.Candlestick C) go.Bar D) go.Waterfall

Answer

**B.** `go.Candlestick` renders financial open-high-low-close data with traditional candlestick markers.

Q9. The gallery's quick-reference decision table maps:

A) Libraries to chart types B) Colors to chart types C) Question types to best chart types D) Datasets to chart types

Answer

**C.** The decision table maps question types ("what are the parts of the whole?", "how does X change over time?") to the best chart type options and alternatives.

Q10. Which gallery category is described as "controversial" because its chart types are often misused?

A) Composition (pie charts) B) Specialized (radar charts) C) Both A and B D) Neither

Answer

**C.** Both pie charts (often misused for too many categories) and radar charts (often misused for data better shown as bars) come with usage warnings in the gallery.

Part II: Short Answer (10 questions)

Q11. Name the 9 question categories in the gallery.

Answer

(1) Comparison, (2) Composition, (3) Distribution, (4) Relationship, (5) Trend, (6) Geospatial, (7) Flow and Network, (8) Part-to-Whole and Ranking, (9) Specialized.

Q12. For a question "how has the proportion of renewable energy changed over the last 20 years?", which gallery chart type is best?

Answer

Stacked area chart (from the Trend category) — shows both the total and the proportional composition over time. Alternative: stacked bar % if showing annual snapshots.

Q13. What are three chart types in the gallery that were NOT covered in earlier chapters?

Answer

Any three of: lollipop, dumbbell, slope, bump, waffle, waterfall, Marimekko, candlestick, radar/spider, gauge, alluvial. These are introduced for the first time in the gallery with enough context to be self-contained.

Q14. When should you NOT use a pie chart?

Answer

When there are more than 5-7 categories (slices become too small to read). When precise comparison matters (people cannot compare angles accurately). When the data does not sum to a meaningful whole. When you want to show change over time (use a line or stacked bar instead).

Q15. Describe the structure of each chart entry in the gallery.

Answer

Each entry has: (1) name, (2) when to use (1-2 sentences), (3) when NOT to use, (4) data requirements, (5) library recommendation, (6) minimal code example (copy-paste-ready), (7) design tips (2-3 bullets).

Q16. What is a bump chart, and when is it appropriate?

Answer

A bump chart shows how rankings change over time. Each entity has a line connecting its rank at each time point. Appropriate for: "which team was ranked first in each year?" Not appropriate for: showing absolute values (use a line chart) or for more than about 15 entities (too many crossing lines).

Q17. What is the difference between a Sankey diagram and an alluvial diagram?

Answer

Both show flows between categories. Sankey diagrams have nodes arranged in stages with ribbon widths proportional to flow magnitude. Alluvial diagrams are similar but specifically show categorical data flowing across parallel axes. In practice, the terms are often used interchangeably; the key difference is that Sankey emphasizes flow magnitude while alluvial emphasizes category membership transitions.

Q18. What is a Marimekko (mekko) chart?

Answer

A Marimekko chart is a 2D chart where bar widths represent one dimension (e.g., market size) and bar heights represent another (e.g., market share). The result is a matrix of rectangles whose areas are proportional to the product of the two dimensions. Useful for showing composition across two categorical dimensions simultaneously.

Q19. How should you use the gallery in practice?

Answer

As a lookup reference: (1) identify your question type, (2) find the matching category in the gallery, (3) browse the 3-8 chart types in that category, (4) choose the best fit, (5) copy the code template, (6) adapt to your data. The gallery is not for linear reading; it is for browsing and copying.

Q20. This is the final question in the final chapter of the book. What is the single most important thing you will take away?

Answer

Personal and subjective. The book's suggested answer: "Process over product — the quality of my visualizations depends on the discipline of my workflow, not just my technical skill." But any honest answer that reflects real learning is correct. The goal of the question is reflection, not a specific answer.

Scoring Rubric

Score	Level	Meaning
18–20	Mastery	You can navigate the gallery fluently and adapt its code to any dataset.
14–17	Proficient	You know the main categories; practice the lookup workflow.
10–13	Developing	Bookmark the gallery and use it actively on your next project.
< 10	Review	Browse the gallery section by section to build familiarity.

This is the final quiz in the book. The gallery is your permanent reference. Use it well.