Accuracy, Readability, and Mplus

The idea to create an algorithm that automatically scans scientific articles for the results of common statistical tests and evaluates the accuracy of these results seems straight-forward. Statcheck performs this, well, stat check. Now a lot of available papers have been automatically evaluated and the outcomes were posted on PubPeer.

So far, none of the (two) papers on pubpeer I co-authored raised an error flag. That’s reassuring. I went and (stat)checked my other publications, and behold: There was indeed an inconsistency in one of them. In Schult et al. (2016) I reported “chi-square(33) = 59.11, p = .004″. Statcheck expected p = .003. The cause of this discrepancy is the rounding of rounded results. The Mplus output showed a chi-square value of 59.109 and a p value of 0.0035. I rounded both values to make the results more readable, accepting that, for example, a value such as 0.00347something would be mistakenly rounded to 0.004 instead of 0.003. For the record: Whenever a test statistic’s p value is close to the chosen alpha level, I do use all available decimal places to evaluate the decision of statistical significance. Of course, I could just report all available digits all the time. Still, that smells of pseudo-accuracy, plus I like to think that I write for human readers, not for computer algorithms.

What’s the take home message here? I won’t be surprised when this error/discrepancy/inconsistency (what’s in a name?) is discovered and posted by the big machine. I will keep writing my papers with care, double-checking the results etc. (something my senior authors always condoned and enforced). And did I mention that I put replication materials online (unless privacy/copyright laws or, sadly, busyness prevent me from doing so)?

Jutze 52 #5 – Gives Girls the Edge

This one was inspired by Self-discipline gives girls the edge: Gender in self-discipline, grades, and achievement test scores (Duckworth & Seligman, 2006). I had the title in mind while I was writing the chorus. Once I had the whole song, I figured I could just write some lyrics about the actual article. A 52-second song certainly cannot do a whole scientific paper justice. But maybe it’s entertaining; and maybe it spreads a tiny bit of knowledge from academia into rock music.

#5 Gives Girls the Edge

Gotta do, gotta do her homework
Gotta do, gotta do her job
Gotta pay, gotta pay attention
Gotta pay, gotta pay her bills
It seems there is one thing, one thing that
Gives girls the edge
Gives girls the edge
Gives girls the edge
Gives girls the edge
Self-discipline gives girls the edge

It seems that boys don’t have the one thing that
Gives girls the edge
Gives girls the edge
Gives girls the edge
Gives girls the edge
Self-discipline gives girls the edge

(words and music by Johannes Schult)