Chart Taxonomy

Goal categories and scored candidate charts from chartTypeMapper.js

VizAdvisor maps each visualization goal to a ranked list of chart candidates. Scores guide the LLM’s candidate evaluation stage and provide a deterministic baseline for tests.

Source of truth: src/utils/chartTypeMapper.js.

1 Goal → candidates

1.1 Comparison

Chart	Score	Best for	Notes
Bar chart	10	nominal, ordinal	Primary
Grouped bar chart	9	nominal, ordinal	Needs ≥2 series columns
Dot plot	7	nominal
Radar chart	4	ordinal	Use only when shape pattern matters; max 10 axes

1.2 Trend

Chart	Score	Best for	Notes
Line chart	10	temporal	Primary
Area chart	8	temporal
Stacked area	6	temporal	≥2 series
Candlestick	5	temporal	Financial domain

1.3 Distribution

Chart	Score	Best for	Notes
Histogram	10	quantitative	Primary
Density plot	9	quantitative
Box plot	8	quantitative
Violin plot	7	quantitative
Beeswarm	5	quantitative	Prefer ≤300 rows

1.4 Correlation

Chart	Score	Best for	Notes
Scatter plot	10	quantitative	Primary
Bubble chart	8	quantitative	≥3 columns
Heatmap	7	quantitative, ordinal
Parallel coordinates	6	quantitative	≥4 columns

1.5 Part-of-whole

Chart	Score	Best for	Notes
Stacked bar	10	nominal, ordinal	Primary
Treemap	8	nominal
Waffle chart	6	nominal	≤4 categories
Pie chart	5	nominal	≤5 categories
Donut chart	5	nominal	≤5 categories

1.6 Geospatial

Chart	Score	Best for
Choropleth map	10	geographic
Symbol map	9	geographic
Dot density map	7	geographic
Flow map	6	geographic

1.7 Network & flow

Chart	Score	Best for
Sankey diagram	10	nominal
Chord diagram	8	nominal
Force graph	7	nominal
Tree / dendrogram	6	nominal

1.8 Ranking

Chart	Score	Best for
Sorted bar chart	10	nominal, ordinal
Lollipop chart	8	nominal
Bump chart	7	nominal, temporal
Slope chart	6	nominal, temporal

2 Golden-path fixtures

Prompt evaluation fixtures under tests/prompts/ encode expected chart families:

Fixture	Goal	Expected primary family
`comparison-goal.json`	Sales by category	bar (must not recommend pie / 3D / rainbow)
`trend-goal.json`	Time series	line / area family
`distribution-goal.json`	Numeric spread	histogram / density / box family

npm run test:prompts

--- title: "Chart Taxonomy" subtitle: "Goal categories and scored candidate charts from chartTypeMapper.js" --- VizAdvisor maps each visualization **goal** to a ranked list of chart candidates. Scores guide the LLM’s candidate evaluation stage and provide a deterministic baseline for tests. Source of truth: `src/utils/chartTypeMapper.js`. ## Goal → candidates ### Comparison | Chart | Score | Best for | Notes | |-------|------:|----------|-------| | Bar chart | 10 | nominal, ordinal | Primary | | Grouped bar chart | 9 | nominal, ordinal | Needs ≥2 series columns | | Dot plot | 7 | nominal | | | Radar chart | 4 | ordinal | Use only when shape pattern matters; max 10 axes | ### Trend | Chart | Score | Best for | Notes | |-------|------:|----------|-------| | Line chart | 10 | temporal | Primary | | Area chart | 8 | temporal | | | Stacked area | 6 | temporal | ≥2 series | | Candlestick | 5 | temporal | Financial domain | ### Distribution | Chart | Score | Best for | Notes | |-------|------:|----------|-------| | Histogram | 10 | quantitative | Primary | | Density plot | 9 | quantitative | | | Box plot | 8 | quantitative | | | Violin plot | 7 | quantitative | | | Beeswarm | 5 | quantitative | Prefer ≤300 rows | ### Correlation | Chart | Score | Best for | Notes | |-------|------:|----------|-------| | Scatter plot | 10 | quantitative | Primary | | Bubble chart | 8 | quantitative | ≥3 columns | | Heatmap | 7 | quantitative, ordinal | | | Parallel coordinates | 6 | quantitative | ≥4 columns | ### Part-of-whole | Chart | Score | Best for | Notes | |-------|------:|----------|-------| | Stacked bar | 10 | nominal, ordinal | Primary | | Treemap | 8 | nominal | | | Waffle chart | 6 | nominal | ≤4 categories | | Pie chart | 5 | nominal | ≤5 categories | | Donut chart | 5 | nominal | ≤5 categories | ### Geospatial | Chart | Score | Best for | |-------|------:|----------| | Choropleth map | 10 | geographic | | Symbol map | 9 | geographic | | Dot density map | 7 | geographic | | Flow map | 6 | geographic | ### Network & flow | Chart | Score | Best for | |-------|------:|----------| | Sankey diagram | 10 | nominal | | Chord diagram | 8 | nominal | | Force graph | 7 | nominal | | Tree / dendrogram | 6 | nominal | ### Ranking | Chart | Score | Best for | |-------|------:|----------| | Sorted bar chart | 10 | nominal, ordinal | | Lollipop chart | 8 | nominal | | Bump chart | 7 | nominal, temporal | | Slope chart | 6 | nominal, temporal | ## Golden-path fixtures Prompt evaluation fixtures under `tests/prompts/` encode expected chart families: | Fixture | Goal | Expected primary family | |---------|------|-------------------------| | `comparison-goal.json` | Sales by category | bar (must not recommend pie / 3D / rainbow) | | `trend-goal.json` | Time series | line / area family | | `distribution-goal.json` | Numeric spread | histogram / density / box family | ```bash npm run test:prompts ``` ## Related docs - [Data Viz Reference](DATA-VIZ-REFERENCE.md) — full encoding principles and pitfalls - [Prompt Design](PROMPT-DESIGN.md) — how the taxonomy feeds Stage 4 candidate evaluation