Fundamentals of Statistics contains material of various lectures and courses of H. Lohninger on statistics, data analysis and chemometrics......click here for more. 
Home Univariate Data Distributions Sampling Distributions F Distribution  
See also: sampling distributions, chisquare distribution, tdistribution  
F Distribution
The Fdistribution becomes relevant when we try to calculate the ratios of variances of normally distributed statistics. Suppose we have two samples with n_{1} and n_{2} observations, the ratio is distributed according to an F distribution (named after R.A. Fisher) with df_{1} = n_{1}1 numerator degrees of freedom, and df_{2} = n_{2}1 denominator degrees of freedom. The Fdistribution is skewed to the right, and the Fvalues can be only positive. Note that three of the most important distributions (namely the normal distribution, the t distribution and the chisquare distribution) may be seen as special cases of the F distribution:


Home Univariate Data Distributions Sampling Distributions F Distribution 
Last Update: 20121008