How many people answered the chocolate suvey?
Before we fit a hierarchical model, we should know how many people answered the survey. The person who answered each question in the chocolate data is identified by a number in the Subject variable. We can find out how many people are described in the data by finding the number of levels of the subject variable. The chocolate data is already loaded. levels() returns a vector with the levels of a factor and length() will tell us the length of the vector.
Deze oefening maakt deel uit van de cursus
Choice Modeling for Marketing in R
Oefeninstructies
- Compute the
length()of thelevels()ofchocolate$Subject.
Praktische interactieve oefening
Probeer deze oefening eens door deze voorbeeldcode in te vullen.
# Determine the number of subjects in chocolate$Subjects