Hello all
Is it possible to constrain parameters to be equal between models in Stata? For example, I have an ordered logistic regression I wish to run for 3 groups and would like to constrain the coefficient of a predictor to be the same in each group on theoretical grounds.
When doing this with linear or logistic regression, I am able to use dummy variables and use the , noconst option to get the desired results simultaneously for each group. However, my outcome variable has 4 levels and so I need to estimate 3 thresholds for each group, whilst constraining the effect of a predictor to be the same in each group (assuming the proportionality assumptions are not violated etc).
Thanks in advance
Ron
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