Could you elaborate on that? What about statistics do you feel makes it necessary to have 1-based indexing?
I've used both 0 based (python, C++), and 1 based (R, matlab, mathematica), but I really belive 1 based is the right choice for Julia. It isn't necessary, but it feels better.
It's mostly about expectations. Users of statistical software, who may or may not be programmers by inclination, use 1-based indexing. The program they came from uses 1-based indexing (R, SAS, Stata, etc.). When you talk about data, you rarely talk about the 0th observation. It's just a recipe for errors to have to code switch between 0 and 1-based indexing.
I am totally fine with zero base in Python and Lisp and such. BUT when I am doing statistics and the math is 1 based I think the ability to make a mistake is to big. Also for subset in R df[1, 1] would be the 2nd row and 2nd column would just throw most users of R.