1. How many levels does fdata contain in the following R code? i. data = c(1 , 2,2,3,1,2 , 3,3 ,1, 2,3,3 , 1) ii. fdata = factor(data) 2. Two vectors, v1 and v2, are created with the following R code:

1. How many levels does fdata contain in the following R code?

i. data = c(1 , 2,2,3,1,2 , 3,3 ,1, 2,3,3 , 1)

ii. fdata = factor(data)

2. Two vectors, v1 and v2, are created with the following R code:

v1

v2

What are the results of cbind (v1, v2) and rbind (v1, v2)?

3. What R command(s) would you use to remove null values from a dataset?

4. What R function is used to encode a vector as a category?

5. What is a rug plot used for in a density plot?

6. An online retailer wants to study the purchase behaviors of its customers. Figure below shows the density plot of the purchase sizes (in dollars). What would be your recommendation to enhance the plot to detect more structures that otherwise might be missed?

7. How many sections does a box-and-whisker divide the data into? What are these sections?

8. What attributes are correlated according to Figure 3-18? How would you describe their relationships?

9. Compare and contrast five clustering algorithms, assigned by the instructor or selected by the student.

10. Using the ruspini dataset provided with the cluster package in R, perform a k-means analysis.

Document the findings and justify the choice of k. Hint: use data(ruspini ) to load the dataset into the R workspace.