# tong2017time-oriented

# Time-oriented Cartographic Treemaps for Visualization of Public Healthcare Data


Tong et al. previously present a novel hybrid visual layout called a cartographic treemap [1], this paper extends it by adding a time variate to it. Time-oriented cartographic treemaps support a visual representation with the following six properties:

  1. Geo-spatial information
  2. Logic Neighborhood Preservation
  3. Hierarchical Data
  4. Multi-variate Data
  5. A Space-filling Layout
  6. Time-dependant Data

On top of cartographic treemap, the work enables the visualization of the temporal evolution trends hidden in EHR data [2].

The authors collaborate with four domain experts in health science throughout the development of the software.


Figure 2 shows an overview of cartographic treemaps with bar charts inside each node, visualizing multiple diagnosis extracted from the EHR data from Public Health England.

User options are provided to replace the bar charts with:

  1. Gradient-oriented bar charts
  2. Symmetric and gradient-oriented bar charts
  3. Line charts
  4. Gradient-oriented line charts

A gradient-oriented bar chart or a gradient-oriented line chart visualizes the change trends in prevalence in different years. A symmetric bar chart raises from the bottom to emphasize the differences between bars. The authors conclude that, as changes are often gradual, line charts are able to provide clearer trends in prevalence rate over years for observations. Filtering is supported for further simplifying visualizations.

Related Work

The work is built upon the previous cartographic treemap algorithm from Tong et al. [1:1].

Data Characteristics

  • Data source: Public Health England
  • Size: over 60,000 records from 209 NHS CCGs
  • Spatial dimensionality: 2D
  • Temporal dimensionality: static
  • Type: multivariate
  • Libraries used: C++

Visualization Techniques

  • Cartographic treemap

Papers Cited


Years Spanned


Application Domain

  • Geospatial Visualization of EHR


  1. Tong, C., Roberts, R., Laramee, R. S., Berridge, D., & Thayer, D. (2017). Cartographic Treemaps for Visualization of Public Healthcare Data. EG UK Computer Graphics & Visual Computing, 1–15. https://doi.org/10.2312/cgvc.20171276 ↩ī¸Ž ↩ī¸Ž

  2. Tong, C., McNabb, L., Laramee, R. S., Lyons, J., Walters, A. M., Thayer, D., & Berridge, D. (2017). Time-oriented Cartographic Treemaps for Visualization of Public Healthcare Data. Computer Graphics & Visual Computing. Retrieved from https://core.ac.uk/download/pdf/132203033.pdf%0Apapers3://publication/doi/10.2312/cgvc.20171276 ↩ī¸Ž

🔄 Last Updated: 7/8/2020, 9:48:18 PM