Regression between cereal sodium and sugar The following figure shows the result of a regression analysis of the explanatory variable x = sugar and the response variable y = sodium for the breakfast cereal data set discussed in Chapter 2 (the Cereal data file on the book’s website).

a. What criterion is used in finding the line?

b. Can you draw a line that will result in a smaller sum of the squared residuals?

c. Now let’s look at a histogram of the residuals. Explain what the two short bars on the far right of the histogram mean in the context of the problem. Which two brands of cereal do they represent? Can you find them on the scatterplot?

d. In general, how reliable would you say amount of sugar is as a predictor of the amount of sodium?

Transcribed Image Text:

Sodium (mg) 350 300 250 200 150 100 50 0- 0 S 10 Sugar (g) 15 20