Monthly Archives: November 2012

Breathless headline-grabbing press releases based on modest findings. Investigations driven by confirmation bias. Broad generalizations based on tiny samples.

I am talking, of course, about the final report of the Diederik Stapel investigation.

Regular readers of my blog will know that I have been beating the drum for reform for quite a while. I absolutely think psychology in general, and perhaps social psychology especially, can and must work to improve its methods and practices.

But in reading the commission’s press release, which talks about “a general culture of careless, selective and uncritical handling of research and data” in social psychology, I am struck that those conclusions are based on a retrospective review of a known fraud case — a case that the commissions were specifically charged with finding an explanation for. So when they wag their fingers about a field rife with elementary statistical errors and confirmation bias, it’s a bit much for me.

I am writing this as a first reaction based on what I’ve seen in the press. At some point when I have the time and the stomach I plan to dig into the full 100-page commission report. I hope that — as is often the case when you go from a press release to an actual report — it takes a more sober and cautious tone. Continue reading →

The tools we have available to us affect the way we interact with and even think about the world. “If all you have is a hammer” etc. Along these lines, I’ve been wondering what would happen if the makers of data analysis software like SPSS, SAS, etc. changed some of the defaults and options. Sort of in the spirit of Nudge — don’t necessarily change the list of what is ultimately possible to do, but make changes to make some things easier and other things harder (like via defaults and options).

Would people think about their data differently? Here’s my list of how I might change regression procedures, and what I think these changes might do:

1. Let users write common transformations of variables directly into the syntax. Things like centering, z-scoring, log-transforming, multiplying variables into interactions, etc. This is already part of some packages (it’s easy to do in R), but not others. In particular, running interactions in SPSS is a huge royal pain. For example, to do a simple 2-way interaction with centered variables, you have to write all this crap *and* cycle back and forth between the code and the output along the way:

desc x1 x2. Continue reading →

Imagine that you have entered a charity drawing to win a free iPad. The charity organizer draws a ticket, and it’s your number. Hooray! But wait, someone else is cheering too. After a little investigation it turns out that due to a printing error, two different tickets had the same winning number. You don’t want to be a jerk and make the charity buy another iPad, and you can’t saw it in half. So you have to decide who gets the iPad.

Suppose that someone proposes to flip a coin to decide who gets the iPad. Sounds pretty fair, right?

But suppose that the other guy with a winning ticket — let’s call him Pete — instead proposes the following procedure. First the organizer will flip a coin. If Pete wins that flip, he gets the iPad. But if you win the flip, then the organizer will toss the coin 2 more times. Continue reading →