RE: st: mlogtest after mlogit

[Nick Cox <n.j.cox@durham.ac.uk>]

You still don't give the exact -mlogit- command you typed. 

If (a) you can reproduce this problem with a dataset accessible to all, and/or (b) you can spell out exact commands visible to all, it stands a better chance of being solved. Trying to solve the problem without (a) is difficult enough, but we still lack even the second, (b). 

In addition, on checking I find that you have not explained that -mlogtest- is a user-written command (versions in STB and various websites) and you have not explained which version you are using. The authors of -mlogtest- are not active members of Statalist, so you are reliant on people understanding a user-written command they have not written. 

Please re-read the Statalist FAQ before posting. By posting fragmentary questions with incomplete information you are making any attempts to help you frustratingly difficult. 

Nick 
n.j.cox@durham.ac.uk 

Chiara Mussida

Thanks Nick. I'm pleased to clarify the points you raised:
1) yes, the categories are 9 at the end, because the outcome
transition=0 is replaceb completely by the other categories.
2)I didn't do anything between mlogit  - stata command for multinomial
logit estimates - and the related mlogtest. Nonetheless mlogtest works
only after mlogit.

Chiara

On 24 October 2011 13:20, Nick Cox <n.j.cox@durham.ac.uk> wrote:

> I don't understand Muhammad's first comment, which requires a change of the data, or indeed why Chiara even tried it out.
>
> In broad terms, Stata [sic] is having difficulties reconciling different information.
>
> That needs to be explored by looking at what you have said to Stata, through input of data and commands. There is little information in your posts to let anyone help you.
>
> First off, you say that there are 9 categories, but in principle there could be 10, according to your -generate- and -replace- statements, but there could be fewer than that depending on values of variables such as -UE- and on whether later -replace- commands overwrite the results of earlier commands.
>
> Second, and more important: What was the -mlogit- command? Did you do anything to your data between -mlogit- and -mlogtest-?
>
> Nick
> n.j.cox@durham.ac.uk
>
>
> Muhammad Anees
>
> Your test is offered by -wald- option after -mlogtest-. Hope this
> gives you what you needed.
>
> On Mon, Oct 24, 2011 at 3:42 PM, Chiara Mussida <cmussida@gmail.com> wrote:
>
>> Thanks, unfortanately the problem remains also with recode
>
> On 24 October 2011 12:13, Muhammad Anees <anees@aneconomist.com> wrote:
>
>>> try with -recode 0=1 if UE==1- for all your categories, the problem
>>> seems to be because -replace- might not have created the relevant
>>> categories.
>
> On Mon, Oct 24, 2011 at 2:59 PM, Chiara Mussida <cmussida@gmail.com> wrote:
>
>>>> I run I mlogit with a dependent variables for 9 outcome categories. As
>>>> postestimation checks I tried to carry out a test for the equality of
>>>> coefs across categories: mlogtest, c
>>>>
>>>> before despalying the output of thus check, STATA (version 12) says:
>>>>  mlogtest, c
>>>>
>>>> Problem determining number of categories.
>>>>
>>>> what does it mean? my dependent variable, transition, is built as follows:
>>>> ge transition=0
>>>> replace transition=1 if UE==1
>>>> replace transition=2 if UN==1
>>>> replace transition=3 if UU==1
>>>> replace transition=4 if EU==1
>>>> replace transition=5 if EN==1
>>>> replace transition=6 if EE==1
>>>> replace transition=7 if NE==1
>>>> replace transition=8 if NU==1
>>>> replace transition=9 if NN==1
>>>>
>>>> where each outcome is a transition or permanence in each labour market
>>>> state (namely, Unemployment, Employment, Non labour force)
>

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