In Chapter 7, we will learn to split the data set into a training data set and a test data set. To test whether there exist unwanted differences between the training and test set, which hypothesis test do we perform, for the following types of variables:

a. Flag variable

b. Multinomial variable

c. Continuous variable Table 6.11 contains information on the mean duration of customer service calls between a training and a test data set. Test whether the partition is valid for this variable, using ???? = 0.10.