nbvargr.hlp.htm

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help for nbvargr
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Graph variable, poisson & negative binomial probabilities
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 nbvargr varname [if] [in] [, n(integer) graph_options]
 

Description
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nbvargr graphs the observed proportions along
        with the poisson and negative binomial
        probabilities for a count type variable.

        The poisson probabilities are computed
        using an estimate of the poisson mean.  
        The negative binomial probabilities use 
        the same mean and an estimate of the 
        overdispersion parameter.

Options
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n the number of discrete levels to be included.
  The default value of n is 10.

Note
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nbvargr requires that nbprob and pprob be installed.

Examples
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 . nbvargr days
 . nbvargr days, n(15)
  . ^nbvargr days, scheme(s2color) msymbol(i i i)^

Author
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      Philip B. Ender
      UCLA StatisticalConsulting
      enderatucla.edu