# Probability in logistic regression

I come across a practice where the logit (Intercept + beta* variables) is once again input as a independant variable in a single variable logistic regression against dependant variable to get intercept ($I$) and a beta ($B_0$). Finally, probability is calculated: $\frac{1}{1+e^{-(I+B_0\text{logit})}}$.

Why is this done -- since probability can be directly calculated from the logit in the first step?

• Are there different dependent variables in the two models? – Macro Sep 8 '11 at 4:47
• Can you post where you're coming across this? – Fomite Sep 11 '11 at 5:18
• No different dependant variables.. It is the same default variable. I come across this in a prob of default model for auto loan portfolio – Suresh Sep 12 '11 at 4:37