Hi,
I'm wondering whether somebody can help me? I'm currently doing some work
using beta distributions but I have I have been given what to me seems a
non-standard parametrisation for its PDF. Comparing it to the standard pdf
they do not look equivalent and I was wondering whether anyone could tell
me what the consequences of the differences in the formulae are?
Firstly the standard formula,
f(x) = [Gamma(alpha+beta)/Gamma(alpha)Gamma(beta)]x^(alpha-1)(1-x)^(beta-1)
and secondly the other formulation
f(x)
=[Gamma(alpha+beta)/Gamma(alpha)Gamma(beta)]x^(beta-1)(1+x)^(-alpha-beta)
where alpha and beta are the shape parameters and Gamma is the standard
Gamma function.
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Many thanks in advance
Alastair
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