Math Psychology?

[neuropsych76]

Hello, I'm asking this question for my girlfriend

She is a double major in math and psych and wants to know the difference between applied math doctorate programs and quantitative psychology programs. What kinds of things can one do with a applied math degree and quantitative psych and vice versa? We have had trouble finding good information online for what these programs are like other than the specific program websites.

Thank you for any help or direction on where to look for information!