function [fstat] = fstat(dof)

% this is a rough fit to the F statistic (0.01), assuming the denominator has 100 dof.

%f=[3.94,3.09,3.98,3.51,3.21,2.99,2.82,2.69,2.59,2.5,2.07,1.89,1.80,1.74,1.65,1.60];

%n=[1,2,3,4,5,6,7,8,9,10,20,30,40,50,75,100];

% this is a rough fit to the F statistic (0.01), assuming the denominator has infinite dof.

f=[6.63,4.61,3.78,3.32,3.02,2.8,2.64,2.51,2.41,2.31,2.18,2.04,1.88,1.79,1.70,1.59,1.47,1.32,1.0];

n=[1,2,3,4,5,6,7,8,9,10,12,15,20,24,30,40,60,120,1000000];

for i=1:19

if (dof <= n(i))

fstat = f(i-1)+(dof-n(i-1))*(f(i)-f(i-1))/(n(i)-n(i-1));

return

end

end

fstat = f(19);