R help - Oct 2011 - difficulties with MuMIn model generation with coxph

Hi All,

I'm having trouble with the automatized model generation (dredge) function
in the MuMIn package. I'm trying to use it to automatically generate subsets
of models from a global cox proportional hazards model, and rank them based
on AICc. These seems like it's possible, and the Mumin documentation says
that coxph is supported. However, when I run the code (see below), it gives
me the following error message:

Error in UseMethod("logLik") : 
  no applicable method for 'logLik' applied to an object of class
"logical"

##RCode

#read in the data
>data1<-read.table('MaleData500.csv', sep=',', header=T) 
survival<-Surv(data1$Wks.at.dth, data1$Died)

#create the full (global) model, a coxph object
>globemodel<-coxph(survival~  edgeden + pctroad + pctcc90+ pctcc80 +
pctcrsog +  ravine + canfrag + pctoldc,  data=data1)

#evaluate all subsets of models using dredge
>exhausting<-dredge(globemodel, eval=TRUE,
fixed=c("pctroad"),m.max=3,
marge.ex=TRUE, rank="AICc")

Error in UseMethod("logLik") : 
  no applicable method for 'logLik' applied to an object of class
"logical"


any suggestions would be greatly appreciated. The globemodel works on its
own, and prints out a summary just fine. The only thing I can think of is
that in the names of globemodel, there is an attribute called loglik, not
logLik?

Thank you,

Sophie

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Dear Sophie,

The answer is 'typo'. 'dredge' does not have an argument named
'marge.ex'.

k


Dnia 2011-10-25 12:00, r-help-request at r-project.org
pisze:
> Message: 131
> Date: Mon, 24 Oct 2011 17:08:41 -0700 (PDT)
> From: sgilbert<sophielgilbert at gmail.com>
> To:r-help at r-project.org
> Subject: [R] difficulties with MuMIn model generation with coxph
> Message-ID:<1319501321733-3935078.post at n4.nabble.com>
> Content-Type: text/plain; charset=us-ascii
>
> Hi All,
>
> I'm having trouble with the automatized model generation (dredge)
function
> in the MuMIn package. I'm trying to use it to automatically generate
subsets
> of models from a global cox proportional hazards model, and rank them based
> on AICc. These seems like it's possible, and the Mumin documentation
says
> that coxph is supported. However, when I run the code (see below), it gives
> me the following error message:
>
> Error in UseMethod("logLik") :
>    no applicable method for 'logLik' applied to an object of class
"logical"
>
> ##RCode
>
> #read in the data
>
>> >data1<-read.table('MaleData500.csv', sep=',',
header=T)
> survival<-Surv(data1$Wks.at.dth, data1$Died)
>
> #create the full (global) model, a coxph object
>
>> >globemodel<-coxph(survival~  edgeden + pctroad + pctcc90+
pctcc80 +
> pctcrsog +  ravine + canfrag + pctoldc,  data=data1)
>
> #evaluate all subsets of models using dredge
>
>> >exhausting<-dredge(globemodel, eval=TRUE,
fixed=c("pctroad"),m.max=3,
> marge.ex=TRUE, rank="AICc")
>
> Error in UseMethod("logLik") :
>    no applicable method for 'logLik' applied to an object of class
"logical"
>
>
> any suggestions would be greatly appreciated. The globemodel works on its
> own, and prints out a summary just fine. The only thing I can think of is
> that in the names of globemodel, there is an attribute called loglik, not
> logLik?
>
> Thank you,
>
> Sophie
>