One letter:  R

http://www.r-project.org/

(I think that's it.  Anyway, does everything you want and is also a
sort of nice scripting language).

Zed A. Shaw
http://www.zedshaw.com/


On Fri, 2 Dec 2005 17:45:46 +0900
Mike Schwab <michael.schwab / yale.edu> wrote:

> A piece of software that badly needs to be written is an easy-to-use 
> statistics package.  Apparently, in the social sciences the industry 
> standard is this program called SPSS, which is a chore to use, quite 
> expensive, and suffers from all sorts of vestiges that no modern 
> program should.
>