Election data displays

November 4, 2008  |  Edward Tufte
13 Comment(s)

Easily the best map (because of its notable content):
Electoral college outlook, Obama v. McCain, from 2 years ago (mid-October 2006):

 image1
Source: SURVEY USA

Excellent reporting of pre-election polls: Pollster.com graphics and tables. Run by first-rate
scholars of surveys, pollster.com provided individual survey results in a long-run context, which reduces the tendency for partisans and
news reporters to go crazy with every little daily random bounce. The main bias of the media is hyped news, which too rapidly
discounts olds, context, stability, and trends moving at a weekly or monthly pace.

Below, pollster.com graphics for some 550 presidential
election polls for all of 2008, along with summary smoothing lines. Particularly helpful is the visual comparison of all the polls each day on the vertical alignment. Also each new daily addition to the graphic (during the course of the campaign) locates that day in relation to all previous daily polls in the campaign. This graphic provides both overview and detail; in well-designed data displays, there does not have to be a trade-off between a quick-read overview and some detailed data showing the pieces going into the overview. Notice how the stronger colors of the smoothed path are cleanly separated from the lighter daily dots from each poll. Also interesting is the increase in the number of daily polls during 2009.

 image2

Below, here’s a part of accompanying database table, and so on through all 550 surveys:
 image3

The above graphics and tables serve well as models for reporting quantitative evidence in government and business (who might well ask “why aren’t our evidence displays up to pollster.com? And why are we still using PowerPoint templates for data presentations?”) The success of pollster.com on the internet indicates that these displays have met a market and usability test: millions of visitors have come to appreciate intense data presentations that combine both overview and detail.

Below, pollster.com’s display for a state:

 image4

Real Clear Politics provided a well-designed summary table showing the
immediate polls, betting, and electoral college distributions. Most of the mainstream media relied on this table for polling coverage. RCP’s Jay Cost of wrote several thoughtful pieces puzzling over polling data. And pollster.com produced many
high-level and deeply informed discussions of polling methodology. My conclusion: journalists should have relied on both pollster.com and RCP.

Here are some good tables and graphics from RCP on election day:
 image5

Below, a beautiful table from RCP:
 image6

Here’s RCP on Florida; note the betting data:
 image7

All these screen dumps were collected around 2.00pm on election day, November 4, 2008. I should have also picked up the excellent displays of fivethirtyeight.com as well.

Topics: 3-Star Threads, E.T.