Question

MTH 240 – CH 9 Homework                                                                                                    

For each of these problems follow the 6-step Hypothesis Testing Guideline in the CH 9 Power Point. You can use the p-value or the critical value method. You can calculate the test statistic and p-value (Step 4) either by hand using the formulas and tables, with a graphing calculator, or by using StatCrunch. Include the details of your calculations, not just the values. If you use the critical value method, state the critical value instead of the p-value.

3. Among 13,200 submitted abstracts that were blindly evaluated (with authors and institutions not identified), 26.7% were accepted for publication. Among 13,433 abstracts that were not blindly evaluated, 29.0% were accepted (based on data from “Effect of Blinded Peer Review on Abstract Acceptance,” by Ross, et al., Journal of the American Medical Association, Vol. 295, No. 14). Use a 0.05 significance level to test the claim that the acceptance rate is the same with or without blinding.

Answer 1

Test for p_1 = p_2 We want to test whether hypothesis: H_0: p_1 - p_2 = 0 H_a: p_1 - p_2 noteqaualto 0 This is two tailed test. P^_1 = 0.267, n_1 = 13200, p^2_1 = 13200, p^_2 = 0.29, n_2 = 13433 Significance level, alpha 0.05 The test difference in proportion is by pooled sample proportion: p x_1 + x_2/n_1 + n_2 or p^_1 n_1 + p^_2 n_2/n_1 + n_2 and q = 1 = 1 - p p 3524.4 + 3895.57/13200 + 13433 almostequalto 0.278601 implies q almostequalto 0.721399 poled standard Error: SE = squareroot pq/n_1 + pq/n_2 = squareroot (0.278601) (0.721399)/13200 + (0.278601) (0.721399)/13433 almostequalto 0.005494 Test statistic, z_observed = p^_1 - p^^_2/SE = p^_1 - p^_2/squareroot pq/n_1 + pq/n_2 (0.267) - (0.29)/0.005494 almostequalto - 4.186127 almostequalto - 4.19 Test statistic = - 4.19 Since this is upper tailed test, p-value = 2 * p (z < mode x_0 mode) = 2 * p (z