A logistic model for beer demand
The linear model does not fit the data when it comes to predicting purchase probabilities. You need a response function that bounds the model predictions between zero and one.
The logistic response function can do this job for you. Therefore, you will need the function glm()
. The function glm()
works very similar to the lm()
function. The main difference is the additional family
argument. As HOPPINESS
is a binary variable, you have to specify the family
argument as binomial
.
This exercise is part of the course
Building Response Models in R
Exercise instructions
- Explain
HOPPINESS
byprice.ratio
using the functionglm()
and the argumentfamily = binomial
. Assign the result to an object namedlogistic.model
. - Obtain the coefficients of the
logistic.model
by using the functioncoef()
.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Explain HOPPINESS by price.ratio
___ <- ___(___, family = ___, data = choice.data)
# Obtain the coefficients