Advanced charts
Advanced charts are a powerful way to display complex data sets. While less intuitive than basic charts, the visualizations should still tell a story the user can understand.
Alluvial diagram
Alluvial diagrams are a type of flow diagram that represents changes in network structure over time.
![Alluvial diagram Alluvial diagram](/static/b05d259ba5784549fa0fcce74fe819d1/3cbba/charts-adv-alluvial.png)
Example of an alluvial diagram
Heatmap
A heat map is a graphical representation of data where individual values contained in a matrix are represented as colors.
![Horizontal bar chart Horizontal bar chart](/static/7e205919a6bd7d99b6584f25f7895e03/3cbba/charts-adv-heatmap.png)
Tree diagram
A tree diagram visually represents a hierarchy in a tree-like structure.
![Tree diagram, organic view Tree diagram, organic view](/static/0fae5c2239e80d5f715c056c6204e336/3cbba/charts-adv-treediagram.png)
Tree diagram, node view vs. list view
Geography with overlays
Choropleth map
A choropleth map uses differences in shading, coloring, or the placement of symbols within predefined areas to indicate the average values of a property or quantity in those areas.
![Choropleth map Choropleth map](/static/d31d564171a45b46fa99430952631b33/3cbba/charts-adv-choropleth.png)
Example of a choropleth map
Proportional symbol
Symbols driven by data are overlayed in geographical regions. A common symbol used is a bubble with the area of the circle proportional to its value in the dataset.
![Proportional symbol Proportional symbol](/static/e8ff96a80f4b27b489a20e4cecfd022e/3cbba/charts-adv-proportion.png)
Example of a proportional symbol
Connecting lines
Connection maps display points on a map connected by straight or curved lines.
Connection maps are most useful when showing connections and relationships geographically. They can also be used to display map routes through a single chain of links.
Connection maps are particularly powerful when revealing spatial patterns through the distribution of connections or by how concentrated connections are on a map.
![Connecting lines on a spatial map Connecting lines on a spatial map](/static/7fa540e390ac5debf9e387563f993c1f/3cbba/charts-adv-connecting.png)
Example of a map with connecting lines