Hi Dann, there is probably a better way to do this, but this works anyway:
# your data gamdat <- rgamma(10000, shape=1, rate=0.5) # comparison to gamma: gamsam <- rgamma(10000, shape=1, rate=0.6) qqplot(gamsam,gamdat) abline(0,1) greetings Remko ------------------------------------------------- Remko Duursma Post-Doctoral Fellow Centre for Plant and Food Science University of Western Sydney Hawkesbury Campus Richmond NSW 2753 Dept of Biological Science Macquarie University North Ryde NSW 2109 Australia Mobile: +61 (0)422 096908 On Tue, Jan 27, 2009 at 3:38 AM, Dan31415 <d.m.mitch...@reading.ac.uk> wrote: > > I'm looking for goodness of fit tests for gamma distributions with large data > sizes. I have a matrix with around 10,000 data values in it and i have > fitted a gamma distribution over a histogram of the data. > > The problem is testing how well that distribution fits. Chi-squared seems to > be used more for discrete distributions and kolmogorov-smirnov seems that > large sample sizes make it had to evaluate the D statistic. Also i haven't > found a qq plot for gamma, although i think this might be an appropriate > test. > > in summary > -is there a gamma goodness of fit test that doesnt depend on the sample > size? > -is there a way of using qqplot for gamma distributions, if so how would you > calculate it from a matrix of data values? > > regards, > Dann > -- > View this message in context: > http://www.nabble.com/Goodness-of-fit-for-gamma-distributions-tp21668711p21668711.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org 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. > ______________________________________________ R-help@r-project.org 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.
