Draw a scatterplot matrix of Speed, Feed, Life, and log(Life), the logarithm of tool life. Add a little jittering to Speed and Feed to reveal over plotting. The plot of Speed versus Feed gives a...

Draw a scatterplot matrix of Speed, Feed, Life, and log(Life), the logarithm of tool life. Add a little jittering to Speed and Feed to reveal over plotting. The plot of Speed versus Feed gives a picture of the experimental design, which is called a central composite design. It is useful when we are trying to find a value of the factors that maximizes or minimizes the response. Also, several of the experimental conditions were replicated, allowing for an estimate of variance and lack-of-fit testing. Comment on the scatterplot matrix.