请问各位：我在用probit回归的时候，出现如下结果，但是就是一直出不来结果，是怎么回事呢
Iteration 0:   log likelihood =  -3040.353  
Iteration 1:   log likelihood = -2255.4113  
Iteration 2:   log likelihood = -2234.2656  
Iteration 3:   log likelihood = -2234.1027  
Iteration 4:   log likelihood = -2234.0995  
Iteration 5:   log likelihood = -2234.0992  
Iteration 6:   log likelihood = -2234.0992  (not concave)
Iteration 7:   log likelihood = -2234.0992  (not concave)
Iteration 8:   log likelihood = -2234.0992  (not concave)
Iteration 9:   log likelihood = -2234.0992  (not concave)
Iteration 10:  log likelihood = -2234.0992  (not concave)
Iteration 11:  log likelihood = -2234.0992  (not concave)
Iteration 12:  log likelihood = -2234.0992  (not concave)
Iteration 13:  log likelihood = -2234.0992  (not concave)
Iteration 14:  log likelihood = -2234.0992  (not concave)
Iteration 15:  log likelihood = -2234.0992  (not concave)
Iteration 16:  log likelihood = -2234.0992  (not concave)
Iteration 17:  log likelihood = -2234.0992  (not concave)
Iteration 18:  log likelihood = -2234.0992  (not concave)
Iteration 19:  log likelihood = -2234.0992  (not concave)
Iteration 20:  log likelihood = -2234.0992  (not concave)
Iteration 21:  log likelihood = -2234.0992  (not concave)
Iteration 22:  log likelihood = -2234.0992  (not concave)
Iteration 23:  log likelihood = -2234.0992  (not concave)
Iteration 24:  log likelihood = -2234.0992  (not concave)
Iteration 25:  log likelihood = -2234.0992  (not concave)
Iteration 26:  log likelihood = -2234.0992  (not concave)
--Break--