[R] mlogit

[David Winsemius]

Looks like a problem that the maintainer should be copied with:

 > maintainer("mlogit")
[1] "Yves Croissant <yves.croissant at let.ish-lyon.cnrs.fr>"

Not sure why it should affect your systems and not mine, but here is  
my sessionInfo() if it helps:

 > sessionInfo()
R version 2.10.1 RC (2009-12-09 r50695)
x86_64-apple-darwin9.8.0

locale:
[1] en_US.UTF-8/en_US.UTF-8/C/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] splines   stats     graphics  grDevices utils     datasets  methods
[8] base

other attached packages:
[1] mlogit_0.1-2    maxLik_0.6-0    mgcv_1.6-1      gdata_2.6.1
[5] Design_2.3-0    Hmisc_3.7-0     survival_2.35-7 chron_2.3-33

loaded via a namespace (and not attached):
[1] cluster_1.12.1     grid_2.10.1        gtools_2.6.1        
lattice_0.17-26
[5] Matrix_0.999375-32 nlme_3.1-96        tools_2.10.1

On Mar 7, 2010, at 12:50 PM, Peter Ehlers wrote:

> On 2010-03-07 10:30, David Winsemius wrote:
>>
>> On Mar 7, 2010, at 12:06 PM, cmc wrote:
>>
>>>
>>>
>>> I am trying to follow this example for multinomial logistic  
>>> regression
>>>
>>> http://www.ats.ucla.edu/stat/r/dae/mlogit.htm
>>>
>>> However, I cannot get it to work properly.
>>>
>>> This is the output I get, and I get an error when I try to use the  
>>> mlogit
>>> function. Any ideas as to why this happens?
>>>
>>>
>>>
>>>> mydata <- read.csv(url("http://www.ats.ucla.edu/stat/r/dae/mlogit.csv 
>>>> "))
>>>> attach(mydata)
>>>> names(mydata)
>>> [1] "brand" "female" "age"
>>>> library(mlogit)
>>> Loading required package: Formula
>>> Loading required package: statmod
>>>>
>>>> mydata[1:10,]
>>> brand female age
>>> 1 1 0 24
>>> 2 1 0 26
>>> 3 1 0 26
>>> 4 1 1 27
>>> 5 1 1 27
>>> 6 3 1 27
>>> 7 1 0 27
>>> 8 1 0 27
>>> 9 1 1 27
>>> 10 1 0 27
>>>> mydata$brand<-as.factor(mydata$brand)
>>>> mldata<-mlogit.data(mydata, varying=NULL, choice="brand",  
>>>> shape="wide")
>>>>
>>>> mldata[1:10,]
>>
>> You do not get the same result as the example page, (while I do). You
>> need to see if you have other objects with names that may be  
>> confusing
>> the interpreter. I did not attach() mydata, which despite the  
>> UCLA's use
>> of it is considered bad practice in R programming because of frequent
>> obscure bugs that trip up newbies such as us. The errors do not occur
>> when the next commands are run.
>
> I do get the same error (I didn't use attach() either), but I
> can avoid the error if I don't call the mlogit.data() output
> 'mldata'. This seems to be a hardcoded name in mlogit() which
> appears to cause the problem. This works:
>
> mdata<-mlogit.data(mydata, varying=NULL, choice="brand", shape="wide")
> mlogit.model<- mlogit(brand~1|female+age, data = mdata, reflevel="1")
>
> -Peter Ehlers
>
>>
>>> brand female age
>>> 1.1 TRUE 0 24
>>> 1.2 FALSE 0 24
>>> 1.3 FALSE 0 24
>>> 2.1 TRUE 0 26
>>> 2.2 FALSE 0 26
>>> 2.3 FALSE 0 26
>>> 3.1 TRUE 0 26
>>> 3.2 FALSE 0 26
>>> 3.3 FALSE 0 26
>>> 4.1 TRUE 1 27
>>>> mlogit.model<- mlogit(brand~1|female+age, data = mldata,  
>>>> reflevel="1")
>>> Error in as.data.frame.default(data) :
>>> cannot coerce class "call" into a data.frame
>>>> summary(mlogit.model)
>>> Error in summary(mlogit.model) : object 'mlogit.model' not found
>>>>
>>> --
>>
>>
>> David Winsemius, MD
>> West Hartford, CT
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>>
>
> -- 
> Peter Ehlers
> University of Calgary

David Winsemius, MD
West Hartford, CT