Bigger Plates, More Food—Or Is It the Other Way Around?; November 2011; Scientific American Magazine; by ÿÿJohn Allen Paulos; 1 Page(s)

A recent study by researchers at the University of Utah suggested that the amount of food diners in a restaurant consumed was influenced by fork size. I haven’t seen details of the study, but it does remind me that people can draw diametrically opposite conclusions from the same raw data by altering definitions ever so slightly.

If only such contradictory results were contrived and isolated phenomena, but they’re not. When dealing with weakly correlated quantities, we often can come up with spurious trends and associations by artfully defining the size of the categories we use. This has been done recently in studies of violent crime to show that certain categories of crime were changing in the desired direction, and I intend to illustrate the point here with a similar story.