15.34 Swampy Sites II Exercise 11.13 presents data (see data set EX1113) on the rates of growth of vegetation at four swampy underdeveloped sites. Six plants were randomly selected at each of the four sites to be used in the comparison. The data are the mean leaf length per plant (in centimetres) for a random sample of ten leaves per plant.

a. Do the data present sufficient evidence to indicate differences in location for at least two of the dis- tributions of mean leaf length corresponding to the four locations? Test using the Kruskal-Wallis H test with = 0.05. a

b. Find the approximate p-value for the test.

c. You analyzed this same set of data in Exercise 11.13 using an analysis of variance. Find the p-value for the F test used to compare the four location means in Exercise 11.13.

d. Compare the p-values in parts b and c and explain the implications of the comparison.

Transcribed Image Text:

Location Mean Leaf Length (cm) 1 5.7 6.3 6.1 6.0 5.8 6.2 2 6.2 5.3 5.7 6.0 5.2 5.5 3 5.4 5.0 6.0 5.6 4.9 5.2 4 3.7 3.2 3.9 4.0 3.5 3.6