Everyone's been talking about psychologist Uri Simonsohn and his role in the downfall of two scientific fraudsters.
When the story first broke, the methods Simonsohn used that allowed him to spot the dodgy data were mysterious - which only added to the buzz. The paper revealing the approach is now up online and it's a must-read. It's not often a statistics paper offers the train-wrecky schadenfreude of watching two fraudsters' careers come to a well-deserved end.
What's rather disturbing about the article, however, is that it doesn't really contain much that's new, in principle. Simonsohn used statistics to spot data in published papers that was, in effect, 'too good to be true'. He then followed up seemingly dodgy cases with some more stats, using simulations of what real data ought to look like, to verify that it was in fact made up. A simple idea in retrospect but one that's never been tried before. I don't think there's a single "Simonsohn method", rather, the paper uses multiple techniques, each one tailored to the particular data in question.
But it shouldn't have come to this. Someone else ought to have spotted that the data looked dodgy.
Take this table from one of Simonsohn's conquests, a soon-to-be-retractedpaper by Lawrence J Sanna et al:
We now know that the data from Studies 2,3 and 4 were all made up. Each study compared 3 conditions, and what makes these data dodgy is that the standard deviations of the 3 sets of results for each study were almost identical. The chances of that happening are very low and it suggests that someone has (clumsily) made the data up.
I'm going to say that these data are obviously suspicious, at least to anyone who has worked with real data. Maybe you'll say that hindsight is 20/20, but Simonsohn didn't need hindsight and the stats he used were nothing remarkable. I'm not saying that to belittle his achievements, he deserves plenty of credit. But other people deserve blame.
Namely, whoever peer reviewed this paper should have spotted that these data looked unusual - and they should not have needed any special statistical tools to do so.
Simonsohn calls for journals to require that the raw data be made available for all published work, on the grounds that. That's a great idea - and not just because it would help catch bad science: it would facilitate proper research and teaching no end. But Simonsohn didn't need the raw data to detect these cases of fraud - he only checked the raw results to confirm the suspicions based on the published data.
Checking that the data are valid is the job of peer reviewers, and they dropped the ball. Instead Simonsohn had to conduct his own private crusade against fraud... a bit like Batman. Batman is awesome, but the point about Batman is that he's only needed because the police can't or won't cope on their own. He's not a superhero, he's just a guy with the will.
Peer reviewers are the police of science, but all too often, they're asleep on the job. Not just in psychology. Retraction Watch provides plenty of examples of published results in biology that were faked, often in comically crude fashion, and should have been obvious to anyone paying attention.
Peer reviewers are usually anonymous. I wonder if a policy of retrospectively naming and shaming the reviewers when a paper turns out to have been fraudulent, might help motivate them...?