Calculus through multiple integration is pretty much required. Working with joint distributions requires multiple integration and any program that touches any theory will require that. Linear algebra is needed when you get into the theory for linear models so it's pretty important as well. Technically if you hadn't taken linear algebra before the course I took you theoretically could get through it since it started from the basics and worked up (but we went through the basics very fast so if you hadn't dealt with them before it would be a shock). Real analysis is useful for mathematical maturity for a masters but probably isn't *required*. If you're going into a program that touches on measure theory, though, you will definitely want to have seen real analysis before that course (although I knew a few people that hadn't taken it before grad school but took it during the summer before they took measure theory).