One factor in the development of tennis elbow, a malady that strikes fear in the hearts...

One factor in the development of tennis elbow, a malady that strikes fear in the hearts of all serious tennis players, is the impact-induced vibration of the racket-and-arm system at ball contact. It is well known that the likelihood of getting tennis elbow depends on various properties of the racket used. Consider the scatter plot of x = racket resonance frequency (Hz) and y = sum of peak-to-peak acceleration (a characteristic of arm vibration, in m/sec/sec) for n = 23different rackets (“Transfer of Tennis Racket Vibrations into the Human Forearm,” Medicine and Science in Sports and Exercise, 1992: 1134–1140). Discuss interesting features of the data and scatter plot.