MSAN 622
Information Visualization

Homework 3

By Monica Meyer

See Code

UK Automobile Deaths and Serious Injuries: Drivers, Front Passengers and Rear Passengers

Click to Filter:

Total UK Automobile Deaths and Serious Injuries

Functionality

Basic

  • Implemented a multi-series line plot displaying the values over time of drivers, front passengers and rear passengers killed or seriously injured in the UK
  • Implemented a stacked area plot for drivers, front passengers and rear passengers killed or seriously injured over time in the UK

Moderate

  • Added the ability to pan on the stacked area plot (when brushing is on) by dragging the brush across the context bar
  • Added details-on-demand, or hover to show tooltip details on the date and value for the multiline plot

Advanced

  • Implemented brushing on the stacked area plot
  • Added user filtering on the multiline plot

Interactivity Guide

Multi-Line Chart

  • Hover over the lines to show the data point and a tooltip with details
  • Click the checkboxes to trigger filtering. When box is checked, the line is drawn, when the box becomes unchecked, the line referencing that category is removed

Stacked Area Chart

  • Click and drag in the context window to brush and choose an area to show in the focus window
  • Once brush is selected, click and drag the selection to pan through the data
  • Click off of the selected area in the context window to revert back to the original chart

Discussion

As a preprocessing step, I removed extra columns of the data and added a date column in R. This was output to a csv for use in the above visualizations.

For this dataset, I chose to first plot a multi-line chart showing the number of drivers, front passengers and rear passengers killed or seriously injured over time. I added tooltips and showed the data point on mouseover so that the user could easily see what the date and value was at any given point along each line. The tooltips used the same colors as the line for reference as well. The line widths were also changed to make them thicker so that the user could see them more clearly. Lastly, I added checkboxes on top of the chart to allow the user to filter the data by category.

I next decided to show a stacked area plot to see the aggregated data as well as the individual categories. For this graph, I added a legend to explain the colors of the data. I also added a context bar so that the user can easily view sections of the data. For this bar, the user can brush over sections of the full data and can both pan and extend the section being viewed. This allows the user to more closely see the trends in the data.