Question: Unhappy HMO patients. A study of complaints by HMO members compared those who filed complaints about medical treatment and those who filed nonmedical complaints with an SRS of members who did not complain that year. Here are the data on the number who stayed and the number who voluntarily left the HMO:
(a) Find the row and column totals.
(b) Find the percentage of each group who left.
(c) Find the expected counts and check that you can safely use the chi-square test.
(d) The chi-square statistic for this table is χ2 = 31.765. What null and alternative hypotheses does this statistic test? What are its degrees of freedom? How significant is it? What do you conclude about the relationship between complaints and leaving the HMO?