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Re: st: Marginsplot after Poisson regression and negative predicted values
From
James Bernard <[email protected]>
To
[email protected]
Subject
Re: st: Marginsplot after Poisson regression and negative predicted values
Date
Wed, 8 Jan 2014 21:52:20 +0800
Forgot to add that I am not interested in confidence interval. My
dependent variable has maximum of 300. However, the maximum of y axis
on the predicted plot is 1
On Wed, Jan 8, 2014 at 9:47 PM, James Bernard <[email protected]> wrote:
> No, I mean that the Y variable that is a count variable on the y axis
> is negative, while my dependent variable is count variable
>
> On Wed, Jan 8, 2014 at 5:37 PM, Maarten Buis <[email protected]> wrote:
>> I suspect that you mean the confidence interval around the predicted
>> values. It is a known issue with the delta method that is used by
>> -margins- for computing the confidence interval. Generally I would not
>> worry too much about it, as these bounds are failry approximate
>> anyhow, but if you do you can predict the linear predictor with its
>> confidence intervals and transform those to the expected count metric
>> as in <http://www.stata.com/support/faqs/statistics/delta-rule/index.html>.
>>
>> Hope this helps,
>> Maarten
>>
>>
>> On Wed, Jan 8, 2014 at 9:51 AM, James Bernard <[email protected]> wrote:
>>> Hi all,
>>>
>>> I have ran a Poisson model. Then tried to run -margins and
>>> -marginsplot for one of the variables.
>>>
>>> The shape of the graph makes sense. But, the range of predicted values
>>> of the dependent variable (which is a count variable, obviously)
>>> ranges from 1 at its maximum and -6 at its minimum. Is this usual? Am
>>> I doing something wrong?
>>>
>>> Thanks,
>>> James
>>> *
>>> * For searches and help try:
>>> * http://www.stata.com/help.cgi?search
>>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>>> * http://www.ats.ucla.edu/stat/stata/
>>
>>
>>
>> --
>> ---------------------------------
>> Maarten L. Buis
>> WZB
>> Reichpietschufer 50
>> 10785 Berlin
>> Germany
>>
>> http://www.maartenbuis.nl
>> ---------------------------------
>> *
>> * For searches and help try:
>> * http://www.stata.com/help.cgi?search
>> * http://www.stata.com/support/faqs/resources/statalist-faq/
>> * http://www.ats.ucla.edu/stat/stata/
*
* For searches and help try:
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