Tuesday, November 5, 2019

Letter of recommendation: Attack of the Psychometricians

(tl;dr: It's letter of recommendation season, and so I decided to write one to a paper that's really been influential in my recent thinking. Psychometrics, y'all.)

To whom it may concern:

I am writing to provide my strongest recommendation for the paper, "Attack of the Psychometricians" by Denny Borsboom (2006). Reading this paper oriented me to a rich tradition of psychometric modeling – but more than that, it changed my perspective on the relationship between psychological measurement and theory. (It also taught me to use the term "sumscore"* as an insult). I urge you to consider it for a position in your reading list, syllabus, or lab meeting.

I first met AotP (or Attack!, as I like to call it) via a link on twitter. Not the most auspicious beginning, but from a quick skim on my phone, I could tell that this was a paper that needed further study.

The paper presents and discusses what it calls the central insight of psychometrics: that "measurement does not consist of finding the right observed score to substitute for a theoretical attribute, but of devising a model structure to relate an observable to a theoretical attribute." In other words, the goal is to make models that link data to theoretical quantities of interest. What this means is that measurement is essentially continuous with theory construction. By creating and testing a good measurement model, you're creating and testing a key component of a good theory.