Bookmark and Share

Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: why does stata creates missing values when running zinb model

From   Maarten Buis <>
Subject   Re: st: why does stata creates missing values when running zinb model
Date   Wed, 19 Oct 2011 11:35:38 +0200

Given that you used an if condition I assume that your dataset
actually contains more observations than just women who are less than
40. If you type after your -zinb- model -count if !e(sample)-, do you
get 31478? If that is the case than there is probably no problem. (In
that case someone at StataCorp forgot a -quietly-.)

-- Maarten

On Wed, Oct 19, 2011 at 10:44 AM, Ekaterina Hertog
<> wrote:
> Dear All,
> I am trying to run a zero inflated negative binominal model in Stata 11. My
> dataset contains 13440 women below 39 who are marriage agency customers. The
> customers of the agency HAVE to provide information on all the major
> demographic variables so there are no missing values on key variables (age,
> height, income, education etc). My dependent variable is nbidder which
> stands for the number of offers a given customer received over the past
> year. About 25% of women did not receive any offers (nbidder=0)
> The command I typed is:
> zinb nbidder prsexrat20441539 ciunmsexrat2039 guntotot age agesq bmi divwid
> havechildren lninc university smoker if age<=39 & sex==2, nolog inf(age
> agesq bmi havechildren lninc university) exposure(duration)
> prsexrat20441539 ciunmsexrat2039 are measures of local sex ratio for each
> customer and guntotot measure how rural the area is.
> Once I run the command I get a message (31478 missing values generated). I
> will be very grateful for any advice of why this may be happening,
> Ekaterina
> On 19/10/2011 00:28, Nick Cox wrote:
>> You fail to tell us anything whatsoever about your data (except that
>> the number of observations presumably is at least 3000) and you do not
>> tell us even the exact command you typed. This is quite contrary to
>> all the advice given to you in the FAQ and in particular repeated on
>> the list within the last 24 hours.
>> -set trace on- will show you where what you think is a problem occurs.
>> If the resulting log is long you may need to edit it for Statalist.
>> Otherwise why not liaise with Stata technical support directly? As
>> above, they will want to know about your dataset.
>> Nick
>> On Tue, Oct 18, 2011 at 11:20 PM, Ekaterina Hertog
>> <>  wrote:
>>> Dear All,
>>> I am trying to run a zero inflated negative binominal zinb model in Stata
>>> 11
>>> and the first output Stata gives me is: 3000 missing values generated. I
>>> am
>>> not sure why this is happening and it sounds wrong, but I cannot find out
>>> what exactly this means and hence how to solve the underlying problem.
>>> Any
>>> advice will be greatly appreciated,
>> *
>> *   For searches and help try:
>> *
>> *
>> *
> *
> *   For searches and help try:
> *
> *
> *

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

*   For searches and help try:

© Copyright 1996–2018 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   Site index