The mechanical aptitude scores of different classifications of workers are as follows:
(a) Test the null hypothesis that test score is independent of job classification. Use a = .05 and a = .01.
(b) Translate each observed frequency into a proportion relative to its row frequency. Do the same for the expected frequencies. Comparing the two, and in view of your answer to (a), what interpretation appears likely?
(c) Calculate the strength of association, .
(d) Calculate effect size, w.