When you want to use by var: command you need to first sort var before using the by; however, it is possible to the by and the sort into a…
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There is an ATS developed program called pprob that will generate a table of poisson probabilities. You can install pprob over the internet by typing search nbvargr (see How can…
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I have to do an analysis of variance on some test scores that were given to me as percentile scores. My question is, “How should I analyze percentile rank data?”…
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This page shows some examples on how to generate the predicted count from a zero-inflated Poisson or a zero-inflated negative binomial model based on the parameter estimates. Zero-inflated models allow…
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Let’s start off by down loading some data and running a binary mixed model with random intercepts and slopes. use https://stats.idre.ucla.edu/stat/data/hsbdemo, clear meqrlogit honors read i.female || cid: read, var…
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Profile analysis is performed using the manova command. The “trick” in doing profile analysis is to do transformations of the dependent variables, using the ytransform option, to allow for the…
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A profileplot graphs the levels of several variables for two or more groups. One can then compare the profiles of the groups to one another. The user-written a command called…
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This FAQ is an elaboration of a FAQ by Allen McDowell of StataCorp. and Nicholas J. Cox of Durham University.  Please see  www.stata.com/support/faqs/stat/logit.html for the original. Proportion data has values…
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We present three examples for three different types of data structures. Let’s first create a sample data set. Each of the examples below will be based on some version of…
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The short answer is that you interpret quantile regression coefficients just like you do ordinary regression coefficients. The long answer is that you interpret quantile regression coefficients almost just like…
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