14. Pedestrian light experiment (Larry Lesher, 1985)

Larry Lesher ran this experiment in order to determine whether pushing a certain pedes-

trian light button had an effect on how long he had to wait before the pedestrian light showed "walk." The treatment factor of interest was the number of pushes of the but-

ton, and 13 observations were taken for each of 0, 1, 2, and 3 pushes of the button. The waiting times for the "walk" sign for the first 32 observations in the order collected are shown in Table 3.12, giving r₀ = 7, r₁ = r₂ = 10, r₃ = 5 (where the levels of the treatment factor are coded as 0, 1, 2, 3 for simplicity). The observations were taken as close together as possible on a Saturday in February 1985.