It has been said - and there is some debate (http://en.wikipedia.org/wiki/Lies,_damned_lies,_and_statistics) as to the origin of this quote - that there are three kinds of untrtuths: "Lies, damned lies, and statistics."
Well I think it's time to extend this a bit further. There are actually four kinds of untruth: "Lies, damned lies, statistics, and information graphics". Statistics can be used to generate some pretty funky or even improbable numbers. Because most people are unfamiliar with the underlying mathematics, they must simply take it on faith that the people who know are both accurate an honest. For the researcher. statistical results are usually reported with numbers. But when they are presented to others they often get translated into graphics, illustrations, pie charts and other sorts of junk, which can easily lead to misinterpretations. Because visual graphics compellingly take advantage of our visual processing abilies, we tend to forget that they can be misleading. Not only ore there problems with perception (think of all of the optical illusions you may have seen before), but there are simple problems of misleading representations.
Pie charts are the worst, especially for making comparisons. usig false perspective, or misleading manipulations of scale can also cause misinterpretations. And needless graphics can be visually distracting.
Fortunately, one doesn't have to be a mathematician to avoid the trouble with misleading information graphics. Some simple principles can help anyone to weed out the lies from the truths. Edward Tufte has a very nice summary of the possibilities in his excellent series of books. The data-to-ink ratio is probably one of the best ways of avoiding problems. Use only enough ink (or pixels) as necessary to communicate the data. Everything else is extraneous and possible confusing.
Just a little thought about this can help one to avoid troubles and falling for the damned lies...
