Chapter 11, Section 11.4.4

 

Arthritis Clinical Trial

Proportional Odds (Ordinal) Regression Model

 

use "arthritis.dta"

 

ologit y4 age trt

 

Iteration 0:   log likelihood = -413.42842

Iteration 1:   log likelihood = -407.07573

Iteration 2:   log likelihood = -407.05473

Iteration 3:   log likelihood = -407.05473

 

Ordered logistic regression                       Number of obs   =        293

                                                  LR chi2(2)      =      12.75

                                                  Prob > chi2     =     0.0017

Log likelihood = -407.05473                       Pseudo R2       =     0.0154

 

------------------------------------------------------------------------------

          y4 |      Coef.   StdErr.      z    P>|z|     [95% Conf. Interval]

-------------+----------------------------------------------------------------

         age |   .0204812   .0098323     2.08   0.037     .0012103    .0397521

         trt |  -.6078954   .2142221    -2.84   0.005    -1.027763   -.1880279

-------------+----------------------------------------------------------------

       /cut1 |  -1.211765   .5316308                     -2.253742   -.1697877

       /cut2 |   .5251197   .5248857                     -.5036373    1.553877

       /cut3 |   2.149424    .538061                      1.094844    3.204005

       /cut4 |   4.136571   .6121251                      2.936828    5.336314

------------------------------------------------------------------------------