Create mlogit.data object
I've pre-loaded the mlogit package and a data frame called chocolate_df that has the chocolate data in long format. We want to fit a choice model to this data, but first we need to convert it to an mlogit.data object. This can be tricky, but it is vital to using mlogit() successfully. Before you start writing code, type head(chocolate_df) directly into the console so that you can refer to the column names.
This exercise is part of the course
Choice Modeling for Marketing in R
Exercise instructions
- Identify the names of the columns where the choice and the alternative numbers are stored. Fill in the names of the columns for the
choiceand thealt.varin themlogit.data()command. - Identify the column numbers where the attributes
Brand,PriceandTypeare stored. Pass these column numbers as a vector for thevaryinginput in themlogitcommand. - Use
str()to confirm that you've converted the data to anmlogit.dataobject.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# use mlogit.data() to convert chocolate_df to mlogit.data
chocolate <- mlogit.data(chocolate_df, shape = "long",
choice = "____", alt.var = "____",
varying = ____)
# use str() to confirm that chocolate is an mlogit.data object