In Exercise 7.15

(p. 360) the solid waste generation rates for cities in industrialized countries and cities in middle-income countries were investigated. In this exercise, the focus is on middle-income countries versus lowincome countries. The next table, extracted from the International Journal of Environmentul Health Research (1994), reports waste generation values (kg per capita per day) for two independent samples. Do the rates differ for the two categories of countries?

a. Which nonparametric hypothesis-testing procedures could bc uscd to answer the question?

b. Specify the null and alternative hypotheses of the test.

c. Conduct the test using a = .01. Interpret the results in the context of the problem.