Hello, I'm looking for a easy way to calculate the quantiles (e.g. 95% quantile) of the inverse chi-squared distribution. This distribution is used as a prior for some bayesian inference calculation, which I want to achieve analyticaly. Is it possible to calculate it through the inverse cdf option of the chi-squared function (qchisq)? The only other functions which I found for the inverse chi-squared are the density and random number generation function invchisq in the geoR-package. If there is no easy way to calculate it, I would be glad if anybody knows where to find a complete set of the tabulated quantiles. Thank you very much. Yours Ekkehart ----------------------------------------------------- Dipl. Geo?kol. Ekkehart Bethge Universit?t Karlsruhe (TH) Graduiertenkolleg Naturkatastrophen Institut f?r Hydromechanik Kaiserstra?e 12 D - 76128 Karlsruhe Phone: ++49 721 608 7793 Email: bethge at ifh.uka.de