Overview
Heatmaps use color to represent values in a matrix or on a map. They are highly effective for identifying patterns, concentrations, and 'hot spots' in large datasets. The variation in color may be by hue or intensity, giving obvious visual cues to the reader about how the phenomenon is clustered or varies over space.
Types
- Grid Heatmap: Used to show relationships between two categorical variables (e.g., sales by day of week and hour of day).
- Spatial Heatmap: Used to show data density on a geographic map (e.g., population density).
Best Practices
- Use a clear and intuitive color scale.
- Provide a legend to explain what the colors represent.
- Ensure the grid is labeled clearly.