--
Martin,
Try: http://www.iser.essex.ac.uk/files/teaching/stephenj/ec968/pdfs/ec968lnotesv6.pdf
I think that's what I already specified, but this time I copied it
right from the link on Stephen's web page, which is:
http://www.iser.essex.ac.uk/iser/teaching/module-ec968
And the book is "lecture notes manuscript" under "Other related
materials, including Lecture notes"
-Steve
On Thu, May 14, 2009 at 11:25 AM, Martin Weiss <[email protected]> wrote:
>
> <>
>
>
> The link to the book does not do much good for me. Is there an alternative?
>
>
>
> HTH
> Martin
>
>
> -----Ursprüngliche Nachricht-----
> Von: [email protected]
> [mailto:[email protected]] Im Auftrag von
> [email protected]
> Gesendet: Donnerstag, 14. Mai 2009 16:58
> An: [email protected]
> Betreff: Re: st: "time ratios" and "hazard ratios"
>
> --
>
> "can I take the multiplicative inverse of the time ratio and report it
> as a hazard ratio?"
>
> No, The (log) Weibull is the only probability distribution for which
> this is true.
>
> It's a good idea to consider multiple probability distributions, as
> you have done. but reporting the regression results is not enough.
> Have you evidence that these distributions fit the data? (using a
> -linktest- or diagnostic plots, for example); that one fits any better
> or worse than the others? You can compare directly the likelihoods of
> the log-logistic and log-normal, and those of the log-normal and
> Weibull models.
>
> For hazard ratio models, I rarely see anything but a Cox model these
> days, because the Weibull has a very restrictive shape. Patrick
> Royston's -stpm- (from SSC) offers a flexible parametric version.
> For the log-linear regression models , the generalized Gamma in Stata
> has the most flexible shape, and its likelihood can be compared
> directly to those of the Weibull and log-normal. See: Stephen
> Jenkins's book “Survival Analysis”, available from his website
> (http://www.iser.essex.ac.uk/teaching/degree/stephenj/ec968/pdfs/ec968lnotes
> v6.pdf
> ).
>
> -Steve
>
> On Wed, May 13, 2009 at 7:16 PM, Emory Morrison
> <[email protected]> wrote:
>> I am reporting different specifications of event history models within the
> same paper.
>>
>> In some of the models (for example the log logistic specification and the
> log normal specification) stata reports coefficients as time ratios.
>>
>> In the Weibull model stata report coefficients as hazard ratios.
>>
>> While the direction of effects are clearly inverted in these two ways of
> reporting the coefficients, I need to know if these coefficients are
> precisely inverse. In other words, can I take the multiplicative inverse of
> the time ratio and report it as a hazard ratio?
>>
>> It would be very helpful in writing up the results of the paper, if the
> coefficients could be read and interpreted in a standardized fashion.
>>
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
