Appendix

Probability Distributions

The uniform distribution on [a,b] has the density

f_{[a,b]}(x) = \{ \begin{array}{cc} \frac1{b-a} & a <= x <= b \\ 0 & {otherwise} \\ \end{array} .

The normal distribution with mean µ and variance sigma^2 has the density

f_{µ,sigma^2(x) = \frac1{\sqrt{2pi} * sigma} * e^{-\frac{(x-µ)^2{2sigma^2

The gamma distribution with parameters (a,lambda) has the density

f_{a,lambda}(x) = \frac{lambda^{a}{Gamma(a)} * e^{-lambda * x} * x^{a-1}    (x>0)

A gamma distribution with parameters (\fracn2,\frac12) is called Chi-Square-distribution with n degrees of freedom, and a gamma distribution with parameters (1,lambda) is called exponential distribution.


If U and V are independent random variables with U ~ N(0,1) and V ~ chi_n^2, then the distribution of T = \fracU{\sqrt{V/n} is called t-distribution with n degrees of freedom and has the density

f_n(x) = \frac1{\sqrt{pi * n} * \frac{Gamma\......ht)} * ( 1 + \frac{x^2n )^{-\frac{n+1}2

If U and V are independent random variables with U ~ chi_{a}^2 and V ~ chi_{b}^2, then the distribution of T = \frac{U/a}{V/b} is called F-distribution with (a,b) degrees of freedom and has the density

f_{a,b}(x) = \frac{a}{b} * \frac{Gamma(\frac{a+b}......rac{a}{b}x )^{\frac{a+b}2   {for} \; x>0


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