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Actinia
Mar 20th, 2007, 04:47 PM
Can anyone point me to a set of statistical probability functions that will give me (say) the probability for a t-test, an F-test or a X2 test. I did find some in the wild on the net, but I am unsure of the legitimacy of using them.

John Rostron

jkd
Mar 20th, 2007, 09:10 PM
I generally just fire up Mathematica and crunch out the integral when I need a particular value of those distributions. I think I saw a Chi^2 calculator in JS once, but it seemed sort of sketchy.

If you are up to the task of writing your own, and you know the integral you need to take, just Taylor expand the integrand out "sufficiently far" (by hand), integrate the resulting polynomial (which is easy to do analytically), and this gives you your JS function which you can plug in the values. Or you could be fancy and do some quadrature or Runge-Kutta techniques to approximate the integral. All of those aren't particularly difficult to write in JS.