Repeat Exercises 18-22 using k-means with k = 4.
Exercise 18
Use k-means with k = 3 to generate a cluster model with the training data set.
Exercise 19
Generate a silhouette plot of your cluster model.
Exercise 20
Calculate the mean silhouette values for each cluster, as well as the overall mean silhouette for the cluster model.
Exercise 21
Provide a two-dimensional scatter plot, using variables of your choice, with an overlay of cluster membership. Choose variables that result in an interesting plot. Note where the cluster boundaries are close, and where they are not so close.
Exercise 22
Using the same variables as the previous exercise, provide a two-dimensional scatter plot, with an overlay of binned silhouette values, as shown in this chapter. Comment on the relationship between your two scatter plots.