On 07-Aug-07 10:27:06, Luis Ridao Cruz wrote: > R-help, > > I'm trying to work out the density function by doing: > >> df(5.22245, 3, 22) > [1] 0.005896862 > >> df(15.20675, 6, 4) > [1] 0.001223825 > > > In excell the result is : > > 0.0071060464 <*> FDIST(5.22245,3,22) > > 0.0100001406 <--> FDIST(15.20675,6,4) > > >>From my point of view the differences in the second case > are substantial. > > Can anyone give me a hint on this? > > Thanks in advance
It would seem that Excel is giving you the upper tail of the F-distribution (cumulative distribution, not density), i.e. what R would calculate as pf(5.22245,3,22,lower.tail=FALSE) [1] 0.007106046 pf(15.20675,6,4,lower.tail=FALSE) [1] 0.01000014 so in effect using "pf" rather than "df". If you want the density function (corresponding to "df") from Excel, then that's not something I know how to do (nor want to know ... ). Best wishes, Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <[EMAIL PROTECTED]> Fax-to-email: +44 (0)870 094 0861 Date: 07-Aug-07 Time: 11:47:52 ------------------------------ XFMail ------------------------------ ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
