Difficulty varies – usually the material is taught at a mathematically elementary level, in some cases requiring little more than arithmetic and perhaps some basic algebra. In other cases you’ll use basic calculus.

However, the biggest stumbling block for students isn’t the mathematical level, it’s usually the fact that its very concept-dense — most first year university courses contain a handful of core "new" tricky but fundamental ideas, whereas in a statistics subject you’ll get about one a week, each building on the ones before. Many of these ideas are non-intuitive for many students. When coupled with the difficulty that it’s often poorly taught, sometimes by people who only half-understand the material (particularly if you’re getting taught within another subject area), it can begin to seem arcane.

It isn’t arcane, though – there’s a handful of simple, powerful ideas underlying much of statistics. It’s just not usually present that way.

How difficult is it – not as difficult as calculus.