I intend to simulate data from gamma distribution. I plan rounding the observations into counts. What I want to know is how I will manipulate the parameters of gamma to have both over and under dispersed count scenarios. [[alternative HTML version deleted]]
Pick the mean (mu) and variance (sig2) you want. Then, shape = mu^2/sig2 and scale = sig2/mu. This should work fine if your mean is large enough so that p(x = 0 or 1) is small. -- View this message in context: http://r.789695.n4.nabble.com/Gamma-count-tp4711845p4711853.html Sent from the R help mailing list archive at Nabble.com.