Average marginal effects
The logistic response function is essentially nonlinear. Therefore, it is not immediately clear what is the effect of a unit change in the price ratio on the probability that a customer purchases Hoppiness. A solution is to interpret the effect of a unit change averaged over all customers.
This average marginal effect can be derived by using the function margins(). The function is loaded from the add-on package margins. Finally, you will compare the average marginal effect for price.ratio of the logistic.model to the price.ratio coefficient of the probability.model.
This exercise is part of the course
Building Response Models in R
Exercise instructions
- Load the add-on package
marginsby using the functionlibrary(). - Obtain the
price.ratiocoefficient for theprobability.modelby using the functioncoef(). - Obtain the marginal effect for
price.ratioof thelogistic.modelby using the functionmargins().
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Load the margins package
# Linear probability model
# Logistic model