“Explanation” is this thing that social scientists (or people in their everyday lives, acting like social scientists) do, where some event X happens and we supply a coherent story that concludes with X. Sometimes we speak of an event as “overdetermined,” when we can think of many plausible stories that all lead to X.
My question today is: what is explanation, in a statistical sense?
To understand why this is a question worth asking at all, compare to prediction. Prediction is another thing that we all to, typically in a qualitative fashion: I think she’s gonna win this struggle, I think he’s probably gonna look for a new job, etc. It’s pretty clear how to map everyday prediction into a statistical framework, and we can think of informal qualitative predictions as approximations to the predictions that could be made by a statistical model (as in the classic work of Meehl and others on clinical vs. statistical prediction).
Fitting “explanation” into a statistical framework is more of a challenge.
I was thinking about this the other day after reading a blog exchange that began with a post by sociologist Fabio Rojas entitled “the argo win easily explained”:
The Academy loves well crafted films that are about actors or acting, especially when actors save the day. These films often beat other films. Example: Shakespeare in Love beats Saving Private Ryan; the Kings Speech beats Black Swan, Inception and Social Network. Bonus: Argo had old Hollywood guys saving the day.
Thomas Basbøll commented, skeptically:
If is is so easy to explain, why didn’t you predict it, Fabio? . . . It’s not like you learned anything new about the nominated films over the past 48 hours besides who actually won. Isn’t this just typical of sociological so-called explanations? Once something had happened, a sociologist can “easily” explain it. If Lincoln had won I suppose that, too, would have been a no-brainer for sociology.
I could see where Basbøll was coming from, but his comment seemed to strong to me, so I responded to the thread:
To be fair, Fabio didn’t say “the argo win easily predicted,” he said “explained.” That’s different. For a social scientist to make a prediction is clear enough, but we also spend a lot of time explaining. (For example, after the 2010 congressional elections, I posted “2010: What happened?”.) Explanation is not the same as prediction but it’s not nothing. For a famous example, Freudian theory explains a lot but does not often predict, and Freudianism has lots of problems, but it is not an empty theory. The fact that Fabio could’ve explained a Lincoln win does not make his Argo explanation empty.
But this got me thinking: what exactly is…