Trials completed is a measure of operant behavior that may reflect any motivational differences among groups, but is unlikely to be related to our central measures of impulsivity. To assess whether there were group differences in this dependent variable, we conducted a mixed Experiment (1 or 2) × Sex × Alcohol Preference (High or Low) × Delay (0, 1, 2, 4, or 8) ANOVA on total trials. Main effects of Alcohol Preference F(1,60) = 9.00, p = 0.004 and Experiment F(1,60) = 5.47, p = 0.023 were detected, but Sex was not (p = 0.09). There were no interactions with Sex (ps > 0.21) so data were collapsed across Sex. Experiment interacted with Delay F(4.0,240.0) = 5.71, p < 0.001, so the 2 experiments were analyzed separately. In experiment 1, there was no main effect of Delay (p = 0.06) or Line (p = 0.12), nor was there an interaction of Delay and Line (p = 0.62). In experiment 2, main effects of Delay F(3.4,113.7) = 5.40, p = 0.001, Line F(1,33) = 6.96, p = 0.013 and an interaction
