# Talk:Proportional hazards model

WikiProject Statistics (Rated Start-class, High-importance)

This article is within the scope of the WikiProject Statistics, a collaborative effort to improve the coverage of statistics on Wikipedia. If you would like to participate, please visit the project page or join the discussion.

Start  This article has been rated as Start-Class on the quality scale.
High  This article has been rated as High-importance on the importance scale.

## terrible page

it doesnt describe any details about the model —Preceding unsigned comment added by 212.186.126.215 (talk) 02:11, 24 October 2008 (UTC)

Wikipedia already has a good article on survival analysis, but it does not mention proportional hazards. I hope that this article will supplement that article; and I hope that it will be useful to users who search for proportional hazards, and fail to find even the survival analysis page.

I also hope this page will be expanded by another editor, or merged with the survival analysis page. --Pstevens 17:39, 30 May 2006 (UTC)

Weibull is a special case of Cox (with specified baseline hazard). Also there is new work in time-dependent covariates. Updating. —Preceding unsigned comment added by 128.59.109.171 (talk) 21:46, 13 May 2009 (UTC)

I just donated \$35 to Wikipedia, then I went looking for an understandable explantation of what a "Cox proportional hazard model" is; unfortunately, I got sent to this entry, which has succeeded only in deepening my mystification. Please, somebody, take pity on those of us who need more fundamental understanding, and write an introduction to this subject that would be useful and graspable by anybody with the basic interest to look it up. That's how to make Wikipedia better; make it useful.Trigley (talk) 20:02, 12 December 2009 (UTC)

It's not at all clear to me what "PH models" and "GLM models". Can someone familiar with these things clarify that sentence? — Preceding unsigned comment added by 136.152.129.247 (talk) 23:53, 31 October 2011 (UTC)

I've just expanded those initialisms, giving "proportional hazards models" and "generalized linear models." Qwfp (talk) 11:55, 1 November 2011 (UTC)

The score "function" is called the score vector and it should use a nabla ($\nabla$) symbol. Also, while the Newton-Raphson method is certainly applicable, many other numerical optimization routines might be applied. In particular, the BHHH optimization algorithm is applicable, making use of only the outer product of the score vectors in approximating the Hessian. Moreover, it doesn't seem very pedagogical to present the Cox Proportional Hazards model with the partial likelihood function without ever mentioning what the full likelihood for this model is (the full likelihood would need a parametric specification of the baseline function $\lambda_{0}(t)$ as well but maximizing over the partial likelihood gives valid estimates of the parameters). Superpronker (talk) 14:10, 11 April 2012 (UTC)

## Proportional Hazards assumptions

There should be a description of the assumptions needed for this model — Preceding unsigned comment added by Bakerstmd (talkcontribs) 19:36, 9 December 2013 (UTC)