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278 PART III: Experimental Methods(c) Using the subtraction method, the difference between the actual-guilt and actual-innocent conditionsin the guilty-expectation condition is 0.16 (3.54 3.70). In the innocent-expectationcondition, this difference is 0.12 (2.54 2.66). Because these differences are very similar,an interaction effect is unlikely.2 (a) Expect guilty: M 9.84, Expect innocent: M 8.74(b) The difference between the means for the expect-guilty and expect-innocent conditions is1.1 (i.e., approximately 1 more persuasive technique in the expect-guilty condition than inthe expect-innocent condition). In contrast, for the statistically significant main effect of thesuspect-status independent variable, the difference in the number of persuasive techniquesused between actual-guilt and actual-innocent conditions is 4.27 (11.42 7.15).(c) An interaction effect is unlikely. Using the subtraction method, the difference betweenthe actual-guilt and actual-innocent conditions in the guilty-expectation condition(7.71 11.96 4.25) is very similar to the computed value for the innocent- expectationcondition (6.59 10.88 4.29).3 (a) Expect guilty: M 6.40, Expect innocent: M 5.70(b) Actual guilt: M 5.60, Actual innocence: M 6.51(c) The statistically significant main effect of the interrogator-expectation variable indicates thateffort to obtain a confession (the dependent variable) was higher in the expect-guilty condition(M 6.40) than in the expect-innocent condition (M 5.70).The statistically significant main effect of the suspect-status variable indicates that effortto obtain a confession was higher in the actual-innocence condition (M 6.51) than in theactual-guilt condition (M 5.60).Answer to Stretching Exercise IIA interaction effect, main effect of the task difficultyB no interaction effect, main effects of task difficulty and anxiety levelC no interaction effect, main effects of type of media and contentD interaction effect, main effects of type of media and contentE interaction effect, main effects of delay and pattern complexity (additional statistical analysesare needed to test these effects)F no interaction effect, main effects of delay and pattern complexityAnswer to Challenge Question 1Dependent Variable10010AB100100b 1b 2b 1Dependent Variable10b 2Dependent Variable10Cb 2b 1a 1 a 2 a 3Aa 1 a 2 a 3Aa 1 a 2 a 3A