Re: st: xtmixed with nonrtolerance. What happens?

[Maarten Buis <maartenlbuis@gmail.com>]

--- "Lukas Boesch"  wrote:
>> The dependent variable is export. The export of wild animal and plant
>> products from one country to the rest of the world. For example: US export of
>> Bears in 1992: 72.
>> Because I cannot sum up the export of different species to one export
>> figure, obviously bears and pearls are not the same, i have to deal with
>> those mixed models. Socioeconomic factors are set as fixed effects and the
>> genus and countries as the variable effects.
>> As one species can be exported by different countries, the data is not
>> hierarchic and country and genus are cross-classified. Or i think this is
>> what it means. Two random effects at the same level for all observations.

I think that your dependent variable is the main reason why your model
is not converging. It is a count and it will probably suffer from lots
of 0s. In that case I would try using -xtmepoisson-. I suspect it will
still not adequately capture the zeros, but it will be better than the
linear model you used.

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany


http://www.maartenbuis.nl
--------------------------
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