Every fall, I get email that read something like this:

I’m writing to inquire about pursuing a Ph.D. in Quantitative Psychology at UW. I’ve always been interested in statistics (data analysis, measurement, etc.). I think that studying quantitative with you would prepare me very well to do research in [insert substantive area here].

I believe I understand the reasoning these students have. “If I learn stats. very well, I’ll be able to do really cool research in social/memory/psychopathology/etc.” Here’s what I wrote a couple weeks ago to someone:

Thanks for your inquiry. You have the right person. However, before I talk about the program, let me ask you something about your email. You wrote that you are interested in stats, but your research interest is on learning and memory. That suggests to me that you should go to a cognitive program where you can focus your research on learning and memory. One of your criteria for choosing a grad. program then might be your ability to get good training in quant. methods and research design.

Why do I raise this? I do because grad. school in Psychology is largely about learning how to do good research. If you were to come to grad. school in Quant. with me, you’d learn how to do research in psychometrics, modeling, and applied stats. That research is performed rather differently than substantive research on learning and memory. Getting a PhD in quant. would not then necessarily put you in a good position to do research on learning and memory. Whereas, if you go to a program and work with an expert in some domain of learning and memory that interests you, you should come out with a solid basis for doing that work. And if you are motivated, you’ll get training in methods that you want. I hope this makes sense. If it doesn’t, feel free to ask clarifying questions.

Let’s make this clearer, If you want to study some substantive psychological domain, you want to learn how to design studies in that domain, how to measure the behavior in question, and how to analyze the acquired data. In Quant. Psychology, you’ll learn how to set up and conduct a simulation study, math stats. and probability theory underlying statistical decisions, computer programming, etc. You’ll also likely do analyses of real data, but often primary interests in quantitative research are about how a quantity or algorithm performed, less on the substantive implications of the specific results. The skills and knowledge for doing good substantive research do not (in my opinion) largely overlap with the skills and knowledge for doing good quantitative research.

In summary, I don’t think pursing a Ph.D. in Quant. is necessarily a good way to try to do great research in some substantive scientific domain. However, if you want to do research on how we measure, model, and study behavior, that is the methods and models used to design our studies and analyze our data, then I think a Ph.D. program in Quant. sounds like a good fit.