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Help on trpois0                                               Hilbe 14Dec1997
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0-Truncated Poisson regression

Command line:

^trpois0^ depvar [varlist] [weight] [^if^ exp] [^in^ range] [, ^lt(^#^) ir^r ^off(^var^) nol^og^ rob^ust ^score^(var)^ cl^uster(var)]

^lt(#)^ = tolerance for convergence ^irr^ = parameter estimates displayed in exponential form; standard errors and CIs adjusted ^off(str)^ = offset variable - log raw var prior to using as offset ^nolog^ = no display of iteration log ^robust^ = displays robust variance estimator; auto w cluster ^cluster(str)^ = identifies variable used for clustering ^score(str)^ = creates a variable with score value

Results may be redisplayed by entering the command. Exponential form and C.I. level are allowed as options without reestimation.

Use: A 0-truncated Poisson model is appropriate when modeling count data which does not have values of 0. This is to be distinguished from data sets without 0 values, but which may have 0's. For example, length of hospital stay data (LOS) begins with patients having a LOS of 1. 0 values are not allowed. This is a situation where a truncated model is appropriate. Examples - --------

. ^trpois0 studytim died drug2 drug3, irr nolog^ . ^trpois0 infected cases cd4 cd8, nolog irr off(cases) cluster(prov)^

. ^trpois0, level(90)^ [redisplay]

Also see - --------

Manual: [5s] poisson, glm, cnreg On-line: help for @poisson@, @glm@, @cnreg@

..- Joseph Hilbe Arizona State University atjmh@@asuvm.inre.asu.edu jhilbe@@aol.com