Exercise

# Likelihood-ratio test

This exercise features a new concept that I haven't covered yet, but I think you are ready for it. *Likelihood ratio tests* are used to compare two models. They tell us whether one model fits the data better than another model, and you can perform this using the `lrtest()`

command, which takes as input two different model objects. We can use it to test whether `choc_m2`

, which has a linear price coefficient, fits the data better than `choc_m3`

, where we treated price as a factor. Those models are already loaded.

Instructions

**100 XP**

Perform a likelihood-ratio test comparing the models `choc_m2`

and `choc_m3`

.