Stata The Stata listserver
[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

Re: st: interpreting coefficients in discrete time hazard model


From   Jenkins S P <[email protected]>
To   [email protected]
Subject   Re: st: interpreting coefficients in discrete time hazard model
Date   Tue, 14 Jan 2003 09:42:59 +0000 (GMT)

On Mon, 13 Jan 2003, Daniel H. Simon wrote:

> Stephen - I just want to double-check, to be sure that I'm clear. The
> interpretation of a coefficient of 5 on ln(x) would be that the hazard rate
> increases by 5% as x increases by 1%. is that right? Thanks again. Daniel

yes (and check out that reference for fuller details about why)

Stephen

> At 11:37 AM 1/13/2003 +0000, you wrote:
> >On Fri, 10 Jan 2003 13:51:37 -0500 Daniel Simon <[email protected]>
> >wrote:
> >
> > > Hi - I am estimating a discrete time hazard model, using pgmhaz.  I have
> > > several covariates that are in the form ln(x).  I'm wondering how to
> > > interpret the coefficients on these variables.  Specifically, when i
> > > exponentiate the estimated coefficient, b, what does exp(b) mean? For
> > > example, if the coefficient b is equal to -5, and exp(-5) is .00674, then
> > > does this say that a 1% change in x reduces the hazard by .99326?  Or
> > is it
> > > something different?  Thanks. Daniel
> >
> >Why might you want to exponentiate the coeff on an explanatory variable
> >that is in log form?  Since -pgmhaz- estimates proportional hazard
> >regression models (using discrete time data), the model is of the form:
> >         log(hazard_it) =  b'X_it + c'log(Y_it)
> >with an additional gamma frailty term in -pgmhaz- Model 2.
> >Hence the coefficient c may be interpreted as the elasticity of the
> >hazard w.r.t. Y_it (or, if you will, the percentage change in the
> >hazard given a one percent change in Y_it:)
> >See the (pdf file) draft lecture notes at
> >http://www.iser.essex.ac.uk/teaching/stephenj/ec968/index.php
> >
> >
> >Stephen
> >----------------------
> >Professor Stephen P. Jenkins <[email protected]>
> >Institute for Social and Economic Research (ISER)
> >University of Essex, Colchester, CO4 3SQ, UK
> >Tel: +44 (0)1206 873374. Fax: +44 (0)1206 873151.
> >http://www.iser.essex.ac.uk
> >
> >*
> >*   For searches and help try:
> >*   http://www.stata.com/support/faqs/res/findit.html
> >*   http://www.stata.com/support/statalist/faq
> >*   http://www.ats.ucla.edu/stat/stata/
>
> *
> *   For searches and help try:
> *   http://www.stata.com/support/faqs/res/findit.html
> *   http://www.stata.com/support/statalist/faq
> *   http://www.ats.ucla.edu/stat/stata/
>
*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/



© Copyright 1996–2024 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index