Hi, I'm doing ordered logistic regression with panel data set, and ran across with the error message that reads "cannot compute an improvement -- discontinuous region encountered"
Following the advice on the previous questions in Statlist, I did my regression model with one, two, (and so on) predictors, and figured out what variable is a trouble maker.
But then, now what? How should I change my model specification?
The age at the first delivery "age_birth" is one of the important independent variables to explain the independent variable of number of the children.


Code:
xtologit children_number age_birth

Fitting comparison model:

Iteration 0:   log likelihood = -8247.2149  
Iteration 1:   log likelihood = -8123.6735  
Iteration 2:   log likelihood = -8123.1374  
Iteration 3:   log likelihood = -8123.1374  

Refining starting values:

Grid node 0:   log likelihood = -5293.4722

Fitting full model:

Iteration 0:   log likelihood = -5293.4722  
Iteration 1:   log likelihood = -3482.5691  
Iteration 2:   log likelihood = -3119.9269  
Iteration 3:   log likelihood = -2363.2178  
Iteration 4:   log likelihood = -2190.7194  
Iteration 5:   log likelihood = -2089.1869  
Iteration 6:   log likelihood = -2041.1365  
Iteration 7:   log likelihood = -2017.9951  (not concave)
cannot compute an improvement -- discontinuous region encountered
r(430);