Gundala Viswanath <gundalav <at> gmail.com> writes: > > Hi all, > > I've tried to plot a vector which has two peaks in the density. > This link shows the figure. > > http://docs.google.com/View?docid=dcvdrfrh_1dk9r2rc7 > > The red line is normal curve and green line is gamma curve. > Notice that red line can correctly fit the histogram that has two peaks > (i.e. red curve also has two peaks). > > But the gamma curve there only has one curve. > > Is there a way I can fit the gamma function such that it also > yields two peaks? >
The gamma distribution is always unimodal (i.e., a single peak). (You call the red line a "normal curve", but it's really a nonparametric density estimate.) You might want to search the list and the available packages for "mixture models", which are a standard way of fitting multimodal distributions ... Ben Bolker ______________________________________________ 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.
