Re: st: RE: logistic tranformation, proportion variables

[Richard Goldstein <richgold@ix.netcom.com>]

Since I am just replying to one issue, I have snipped most of Jay's 
response:

Note that much of the environmetrics literature, but not all, has a 
slightly different problem -- a problem that I also have and have spoken 
with StataCorp about, namely that some of the zeros are censored but 
some are true; thus, there is a mixture distribution and Stata needs to 
go one step further than just -tobit- or -cnreg-.

Rich

Verkuilen, Jay wrote:

> Richard Goldstein wrote:
>
> There is also a large literature in envirometrics on the zeros problem, which goes under the guise of "non-detect analysis." Usually the solution is to use a censored regression model, for which Stata is admirably supplied with tools. Which solution you pick depends a lot on how you see the boundary observation and observed points nearby it (software concerns aside, which in Stata is nearly true, and sample size). 
> JV
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