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.
Este exercício faz parte do curso
Choice Modeling for Marketing in R
Instruções do exercício
- Compute the
length()
of thelevels()
ofchocolate$Subject
.
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
# Determine the number of subjects in chocolate$Subjects