Probability plot for data compared with fitted gamma distribution -----------------------------------------------------------------
^pgamma4^ varname [^if^ exp] [^in^ range] [ ^,^ ^a^lpha^(^#^)^ ^b^eta^(^#^ > )^ ^gr^id graph_options ]
Description -----------
^pgamma4^ produces a probability plot for varname compared with a two-parameter gamma distribution with shape parameter alpha and scale parameter beta. By default, alpha and beta are taken from S_alpha and S_beta, which is where ^gamma4^ puts maximum likelihood estimates of them.
Note: this is the original version of ^pgamma^, written for Stata 4. Users of Stata 8 up should switch to ^pgamma^.
Options -------
^alpha(^#^)^ sets alpha to #.
^beta(^#^)^ sets beta to #.
^grid^ is equivalent to ^yline(.25,.5,.75) xline(.25,.5,.75)^.
graph_options are any of the options allowed with ^graph, twoway^; see help for ^graph^.
Example -------
. ^gamma4 precip^ . ^pgamma4 precip^
Author ------
Nicholas J. Cox, University of Durham, U.K. n.j.cox@@durham.ac.uk
Also see --------
On-line: help for @graph@, @gamma4@, @qgamma4@