Caricatures and credits
A lot of surprisingly popular accounts on Twitter just tweet pictures, without giving any sources,and often with captions that misleading or just wrong. One from yesterday had a picture of a picnic on a highway in the Netherlands in 1973 and described it as being from the US.
Here’s one that came from @AmazingMaps, today, captioned “Most popular word used in online dating profiles by state”
Could it really be true that ‘NASCAR’ is the most popular word in Indiana dating profiles? Or that ‘oil’ is the most popular word in Texas? Have the standard personal-ad clichés become completely outdated? Aren’t Americans easy-going any more? Doesn’t anyone care about romance or honesty or humour?
We’ve seen this sort of analysis before on StatsChat. It’s designed to produce a caricature, though not necessarily in a bad way. This one comes from Mashable, based on analysis by Match.com. The original post says
Essentially, they broke down which words are used with relative frequency in certain states, as compared to relative infrequency in the rest of the country.
That is, the map has ‘oil’ for Texas and ‘NASCAR’ for Indiana not because these words were used very often in those states, but because they were used much less often in other states. Most Indiana dating profiles probably don’t mention NASCAR, but a much higher proportion do than in, say, New York or Oregon. Most Texas dating profiles don’t talk about oil, but it’s more common in Texas than in Maine or Tennessee. It’s not that everyone in Oregon or Idaho kayaks, but a lot more do than in Iowa or Kansas.
When this map first came out, in November, there were lots of stories about it, typically getting things wrong (eg an NBC motor sports site had the headline “NASCAR” is most frequently used word among Indiana online dating profiles”). That’s still bad, but most of these sites had links or at least mentioned the source of the map, so that people who care could find out what the facts are. @AmazingMaps seems confident none of its followers care.
Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »