Answer Happy

2.5 Social experiment, Part I. A "social experiment" conducted by a TV program questioned what people do when they see a very obviously bruised woman getting picked on by her boyfriend. On two different occasions at the same restaurant, the same couple was depicted. In one scenario the woman was dressed "provocatively" and in the other scenario the woman was dressed "conser- vatively". The table below shows how many restaurant diners were present under each scenario, and whether or not they intervened. 0.2 0.1 Intervene 0 Yes No Total -0.4 A simulation was conducted to test if people react differently under the two scenarios. 10,000 simulated differences were generated to construct the null distribution shown. The value ppr,sim represents the proportion of diners who intervened in the simulation for the provocatively dressed woman, and peon,sim is the proportion for the conservatively dressed woman. -0.2 Scenario Provocative 5 15 20 A Conservative 15 10 25 0.0 A Ppr_sim-Pcon_sim Total 20 25 45 0.2 0.4 (a) What are the hypotheses? For the purposes of this exercise, you may assume that each observed person at the restaurant behaved independently, though we would want to evaluate this assumption more rigorously if we were reporting these results. (b) Calculate the observed difference between the rates of intervention under the provocative and conservative scenarios: Ppr - con- (c) Estimate the p-value using the figure above and determine the conclusion of the hypothesis test.