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From |
"Martin Weiss" <martin.weiss1@gmx.de> |

To |
<statalist@hsphsun2.harvard.edu> |

Subject |
AW: st: "time ratios" and "hazard ratios" |

Date |
Thu, 14 May 2009 17:38:53 +0200 |

<> Thank you very much, it works well now! HTH Martin -----Ursprüngliche Nachricht----- Von: owner-statalist@hsphsun2.harvard.edu [mailto:owner-statalist@hsphsun2.harvard.edu] Im Auftrag von sjsamuels@gmail.com Gesendet: Donnerstag, 14. Mai 2009 17:36 An: statalist@hsphsun2.harvard.edu Betreff: Re: st: "time ratios" and "hazard ratios" -- 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 <martin.weiss1@gmx.de> wrote: > > <> > > > The link to the book does not do much good for me. Is there an alternative? > > > > HTH > Martin > > > -----Ursprüngliche Nachricht----- > Von: owner-statalist@hsphsun2.harvard.edu > [mailto:owner-statalist@hsphsun2.harvard.edu] Im Auftrag von > sjsamuels@gmail.com > Gesendet: Donnerstag, 14. Mai 2009 16:58 > An: statalist@hsphsun2.harvard.edu > 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 > <Morrison@soc.msstate.edu> 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/ * * 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/

**References**:**st: "time ratios" and "hazard ratios"***From:*"Emory Morrison" <Morrison@soc.msstate.edu>

**Re: st: "time ratios" and "hazard ratios"***From:*sjsamuels@gmail.com

**Re: st: "time ratios" and "hazard ratios"***From:*sjsamuels@gmail.com

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