Results and Analyses -------------------- Ego depletion replication results Henry Otgaar, Carolien Martijn, Hugo Alberts, Harald Merckelbach, Alexej Michirev & Mark L. Howe Maastricht University Participants We recruited participants (N = 100, males = 14, females = 86, M age = 21.64 years, SD = 2.51) from an undergraduate participant pool at Maastricht University. The participants were bachelor psychology students and participated in the study for payment of 7.50 euro. Participants (n = 2) were excluded from the final analysis because of an error in saving data in E-Prime. The final sample contained 85 females and 13 males (mean age = 21.58 years, SD = 2.42). Specifically, the sample comprised 48 participants in the hard letter ‘e’ (ego-depletion) condition and 50 participants in the easy letter ‘e’ (control) condition. Alexej Michirev served as the experimenter. Because the experimenter read the instruction to participants, he was aware who received the ego depletion or control condition and this deviated from the protocol. For the rest, our procedures followed the approved protocol. Critical analyses 1) Independent samples t-test comparing the ex-Gaussian fitted mean overall response time variability (RTV) for the incongruent items on the MSIT across the ego-depletion and control conditions. Ego-depletion: n = 25; M RTV= 0.28; SD = 0.07; SE = 0.01 Control: n = 44; M RTV = 0.31; SD = 0.07; SE = 0.01 t(67) = -1.68, p = .10, d = .43 2) Independent samples t-test comparing the mean overall response time (RT) for the incongruent items on the MSIT across the ego-depletion and control conditions. Ego-depletion: n = 25; M RT= 0.86; SD = 0.12; SE = 0.02 Control: n = 44; M RT = 0.93; SD = 0.14; SE = 0.02 t(67) = -2.1, p = .04 3) A series of independent samples t-tests comparing participants’ mean ratings of effort, fatigue, difficulty, and frustration across the ego-depletion and control conditions (with positive t’s indicating larger rating in the ego-depletion group). Ego-depletion: Effort, M = 4.81; SD = 1.41; SE = 0.20; Fatigue, M = 3.63; SD = 1.72; SE = 0.25; Difficulty, M = 4.04; SD = 1.46; SE = 0.21; Frustration, M = 3.00; SD = 1.60; SE = 0.23 Control: Effort, M = 3.88; SD = 1.99; SE = 0.28; Fatigue, M = 3.80; SD = 1.60; SE = 0.23; Difficulty, M = 1.76; SD = 0.96; SE = 0.14; Frustration, M = 1.82; SD = 1.22; SE = 0.17 t-tests: Effort (t(96) = 2.67, M difference = 0.93 p = .009, d = 0.54), Fatigue (t(96) = -0.52, M difference = -0.18, p = .60, d = 0.10), Difficulty (t(96) = 9.19, M difference = 2.28, p < .001, d = 1.85), and Frustration (t(96) = 4.11, M difference = 1.18, p < .001, d = 0.83). Supplemental analyses Recommended supplemental analysis An independent samples t-test for differences in overall accuracy on the letter ‘e’ task across the hard (ego-depletion) and easy (control) conditions: Ego-depletion: n = 25; M accuracy = 0.95; SD = 0.04; SE = 0.008 Control: n = 44; M accuracy = 0.99; SD = 0.01; SE = 0.001 t(67) = -6.95, p < .001, d = 1.37