In a new SAS program, use the SAS data set world2 saved in Exercise 2.16 in a proc freq step to do the following:

a. Obtain two-way frequency tables (in the cross-tabulation format)

for the variable Techgrp with Infgrp, Techgrp with Civilgrp, and Popgrp with Infgrp. Compute chi-square statistics, cell χ2, and cell expected values but no column, row, or cell percentages.

b. Obtain a two-way frequency table (in the list format) for Infgrp and Civilgrp.

c. Use the chi-square statistic to test hypotheses of independence between pairs of variables considered in part

(a) and state your results.

d. Use the contingency coefficient C to comment on the strength of association for the pair of variables techgrp and civilgrp.

e. Use the values of gamma, Kendall’s tau-b, and Spearman’s correlation coefficient to comment on the association between Techgrp and Infgrp.

f. Use appropriate measures to evaluate the strength of association between popgrp and infgrp. Considering that popgrp is an independent variable useful for predicting infgrp for each country, interpret the appropriate measures of association. Explain.