I am having issues with an assignment. We are supposed to use the Movies dataset and then split it by rating variable. Afterwards, we are to apply a box cox transformation and shapiro wilks test on the "GrossTake" variable of the split data using one of the "apply" family of functions. I can do those using a single loop but our professor is adamant in using one of those special functions.
#Getting the dataset
library(MindOnStats)
data(Movies)
str(Movies)
head(Movies)
#changing name of dataset
d3 <- Movies
head(d3)
summary(d3)
#packages for Box Cox Transformation
library(Matrix) # ... for matrix operations
library(car) # ... for ellipse plots
library(stats) # ... for statistical operations
library(MASS) # ... for Multivariate Normal Distribution
library(graphics) # ... for arrows
#splitting the data by Rating
d4 <- with(d3,split(d3,Rating))
head(d4)
length(d4)