From p.dalgaard at biostat.ku.dk  Fri Aug 29 23:06:09 2008
From: p.dalgaard at biostat.ku.dk (Peter Dalgaard)
Date: Fri, 29 Aug 2008 23:06:09 +0200
Subject: [Rd] coxph function (Survival Library) (PR#12638)
In-Reply-To: <20080829173012.ECE16282C763@mail.pubhealth.ku.dk>
References: <20080829173012.ECE16282C763@mail.pubhealth.ku.dk>
Message-ID: <48B864C1.5070202@biostat.ku.dk>

ana.marcos at uam.es wrote:
> Hi,
>
> I am pretty sure that the results of Likelihood ratio test are bigger 
> than the real value. They are multiplied for the factor Ln(10), in this 
> way the p-values are smaller than what they should be.
> The reason is that you apply the formula -2*log(exp(L(0)/exp(L(B)) and 
> not  what it should be -2*log(L(0)/L(B)).
>
> Please if I am not right, tell me
>   

I don't think you are and please don't use the bug report system when 
you are not sure.

Notice that the conventions for the default base in "log" differ between 
countries (and even between education levels with countries). There's no 
indication that base 10 logs are used anywhere, so where would a factor 
of ln(10) creep in?

-- 
   O__  ---- Peter Dalgaard             ?ster Farimagsgade 5, Entr.B
  c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
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~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)              FAX: (+45) 35327907



[Rd] coxph function (Survival Library) (PR#12638)
Peter Dalgaard