Refer to Table 7.3 on high school students’ use of alcohol, cigarettes, and marijuana. View the table as matched triplets. a. Construct the marginal distribution for each substance. Find the sample...

Refer to Table 7.3 on high school students’ use of alcohol, cigarettes, and marijuana. View the table as matched triplets.

a. Construct the marginal distribution for each substance. Find the sample proportions of students who used (i) alcohol, (ii) cigarettes, (iii) marijuana.

b. Specify a marginal model that could be fitted as a way of comparing the margins. Explain how to interpret the parameters in the model. State the hypothesis, in terms of the model parameters, that corresponds to marginal homogeneity.