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Calculate Student distribution
http://forum.alglib.net/viewtopic.php?f=2&t=2246		 Page 1 of 1
Author:  alisichkin [ Thu Feb 19, 2015 3:25 pm ]
Post subject:  Calculate Student distribution
Hello!
I need calculate student distribution for example for 8 degree of freedom and confidence probability 0.95
According to the t-distribution table (http://en.wikipedia.org/wiki/Student%27s_t-distribution)
f(8, 0.95)=2.306

I try use alglib::studenttdistribution function. I and what I see:

Code:
#include "specialfunctions.h"

int main(array<System::String ^> ^args)
{
    Console::WriteLine(L"Test");
    Console::WriteLine(L"f(8, 0.05)="+alglib::studenttdistribution(8, 0.05));
    Console::WriteLine(L"f(8, 0.95)="+alglib::studenttdistribution(8, 0.95));
    Console::WriteLine(L"------");
    Console::WriteLine(L"f~(8, 0.05)="+alglib::invstudenttdistribution(8, 0.05));
    Console::WriteLine(L"f~(8, 0.95)="+alglib::invstudenttdistribution(8, 0.95));
    return 0;
}

Result:
Test
f(8, 0.05)=0,519325892460749
f(8, 0.95)=0,815037419273614
------
f~(8, 0.05)=-1,8595480375309
f~(8, 0.95)=1,8595480375309

What I'm wrong?

Alexandr.
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