The index -2LL (minus two times the log likelihood) is used in the context of statistical models (like logistic regression) to assess the fit of the overall model, particularly in the likelihood ratio test. It is not a probability, nor is it a simple transformation of log odds, and it decreases (not increases) as the goodness-of-fit of the model increases.

Solved

The Index -2LL

Question 9

Multiple Choice

The index -2LL:

A) Is a probability that can range from .00 to 1.00
B) Is the transformed value of the log odds
C) Is used as a basis for assessing the fit of the overall model, in the likelihood ratio test
D) Increases in value as the goodness-of-fit of the model increases

Correct Answer: