Parameter Estimates

Looking at the parameter estimates and standard errors, you can see that you have replicated the alternative model from the test of proportional hazards. By explicitly specifying the model, you can request additional parameter statistics and plots. Here we have requested the design effect; the value for t_age of less than 1 indicates that the standard error for t_age is smaller than what you would obtain if you assumed that the dataset was a simple random sample. In this case, the effect of t_age would still be statistically significant, but the confidence intervals would be wider.