Multinomial Logistic Regression - Category Size

Posted by s-volk on Nov 30, 2010; 12:49pm
URL: http://spssx-discussion.165.s1.nabble.com/Multinomial-Logistic-Regression-Category-Size-tp3286013.html

Dear all,

I ran a multinomial logistic regression analysis with one continuous independent variable. I have a sample size of 68 subjects (psychological experiment) which end up split into 5 categories ranging in size from 5 to 24 (dependent variable). The MLR-model has a Nagelkerke R2 of 0.27 and Model Fit χ2=19.71, p<0.01.

Now here is the problem: A reviewer complains that my results may be sample specific because one of the 5 categories of the dependent variable consists of only 5 observations (subjects), i.e. sh/e argues that very few participants (five) are responsible for the observed effects. Is this valid argument? I thought that if the overall model is significant, I can conclude that there is a significant relationship between the dependent and independent variable for all categories of the dependent variable? That is, the calculations for the overall model are based on all observations (68) and not only on the observations in specific categories (e.g., 5)?

I was wondering if someone could provide me with or point me to some arguments for reviewers (ideally including some references)?

Many thanks in advance,
Stefan