Using the data in Exercise 21, perform the Tukey–Kramer test to determine which pairs of means, if any, differ. Use the α = 0.01 level of significance.

Exercise 21

Artificial hip joints consist of a ball and socket.

As the joint wears, the ball (head) becomes rough. Investigators performed wear tests on metal artificial hip joints. Joints with several different diameters were tested. The following table presents measurements of head roughness (in nanometers).

Transcribed Image Text:

Diameter Head Roughness 16 0.83 2.25 0.40 2.78 3.23 28 2.72 2.48 3.80 36 6.49 5.32 4.59