[R] How to compute the P-value for a mixture of chi^2 distributions

[Thomas Lumley]

On Sun, Jun 12, 2011 at 12:44 PM, Tiago Pereira
<tiago.pereira at mbe.bio.br> wrote:

> The test I am working on has an asymptotic 0.5*chi2(1)+0.5*chi2(2)
> distribution, where numbers inside parenthesis stand for the degrees of
> freedom. Is is possible to compute quickly in R the cumulative distribution
> of that distribution?
>

There appear to be pchibar() functions in both the ibdreg and ic.infer
packages that should do want you want.  Simulation is also fairly
efficient.

    -thomas

-- 
Thomas Lumley
Professor of Biostatistics
University of Auckland