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Chetan Nandakumar - Feb 08, 2010 08:22:11 am


This visualization is focused on presenting the needs of Haiti's relief areas to the viewer in a way for him/her to perceive relationships not easily seen otherwise. So there's no specific narrative to this visualization -- it hopes to communicate how Haiti's needs are broken down by area and how well the needs of these different areas are being met.

This visualization is broken into two sections. The first is the graphic on top titled "Aid requirements for Haiti broken down by areas of need. Total = $575 M". This graphic is intended to give the viewer a rough sense of how the needs of different areas relate to the total need (the part-to-whole relationship) and also how different areas relate with one another.

I chose to use a pie chart as I believed it to be the best choice given the goals of this visualization. In a quick glance, the rough part-to-whole relationships are garnered - the user instantly sees that food is the biggest need and that health is a distant second; the user instantly sees that safety and security and rule of law are the smallest needs of the lot.

For the user interested in more detail, the percentages are clearly printed adjacent to each label and the actual dollar requirements are printed below.

Below the top graphic is a graphic entitled "Aid for each area broken down by Uncommited Pledges, Committed Pledges, and Unmet Need." This graphic uses the principle of small multiples where each area from above is broken down by the amount from committed pledges, uncommitted pledges and the unmet requirement. Once again, the pie chart is used in order to communicate the part-to-whole relationships. Graphs are sorted by this variable in a left-to-right, top-to-down ordering. For the viewers interested in greater detail, the respective percentages are printed in each slice and the total need is printed in each graph's title.

The other design choice was to use a stacked bar chart. Stacked bar charts have the advantage of being more accurately parsed by the eye. However I chose against it because I was interested in visualizing three variables: uncommitted pledges, committed pledges and unmet need, and stacked bar charts become confusing in this case. As is described below, some interesting relationships pop out when all three variables are represented.

By using the principle of small multiples, comparisons are facilitated between different relief areas. From this visualization, a viewer instantly sees that most has gone to food, health and coordination, education and infrastructure have received almost nothing and all areas continue to have huge unmet needs. It's also easily seen that most of the pledged money is in fact committed.

In both graphics (top and bottom), color is used to differentiate the different slices of the pie for easy visual parsing.

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