STA 3024 Exam 1 Sample Questions

35. In a chi-squared test, if df = 3, then a test statistic value of X 2 = 20.95 corresponds to a p-value(A) smaller than 0.001.(B) between 0.001 and 0.005.(C) between 0.005 and 0.010.(D) between 0.010 and 0.025.(E) between 0.025 and 0.050.36. A large company is performing random drug testing of its employees, and it wants to see ifthere is a difference in the frequency of drug use between supervisors and lower-level workers.A random sample of 4963 employees yields the following contingency table:Drug Test ResultsEmployee Type Passed Failed TotalSupervisors 265 2 267Lower-Level Workers 4456 240 4696Total 4721 242 4963The percentage of supervisors who failed the drug test is(A) 0.75%.(B) 0.83%.(C) 1.59%.(D) 4.88%.(E) 5.38%.37. A researcher has just used a contingency table to perform a chi-squared test, during which shecalculated a test statistic value of X 2 = 3.110. Later, she decides to be a bad researcher, andshe starts making things up. She decides to say that each subject in her sample was really 10subjects, so she makes a new contingency table that is the same as her original one, but withall the observed counts multiplied by 10. (Clearly this is completely inappropriate, but she doesit anyway.) She then redoes her entire chi-squared test from scratch using this new contingencytable. What will the value of the X 2 test statistic be when she redoes the test?(A) 3.110(B) 31.10(C) 311.0(D) none of the above38. In a chi-squared test, which of the following has a standard normal distribution when H 0 is true?(A) the observed counts(B) the expected counts(C) the row and column totals(D) the relative risk(E) the standardized residuals