| Literature DB >> 34851960 |
Tamás Keller1,2,3, Hubert János Kiss2,4.
Abstract
Motivated by the two-decade-long scientific debate over the existence of the ego-depletion effect, our paper contributes to exploring the scope conditions of ego-depletion theory. Specifically, in a randomized experiment, we depleted students' self-control with a cognitively demanding task that required students' effort. We measured the effect of depleted self-control on a subsequent task that required self-control to not engage in fraudulent cheating behavior-measured with an incentivized dice-roll task-and tested ego-depletion in a large-scale preregistered field experiment that was similar to real-life situations. We hypothesized that treated students would cheat more. The data confirms the hypothesis and provides causal evidence of the ego-depletion effect. Our results provide new insights into the scope conditions of ego-depletion theory, contribute methodological information for future research, and offer practical guidance for educational policy.Entities:
Mesh:
Year: 2021 PMID: 34851960 PMCID: PMC8635394 DOI: 10.1371/journal.pone.0260141
Source DB: PubMed Journal: PLoS One ISSN: 1932-6203 Impact factor: 3.240
Descriptive statistics.
| Baseline variables measured before the treatment | Treatment | Outcome variables: Cheating | Less valuable gift [fatigue] | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Girl | Age | N of books | GPA | Disruptive school beh. | Math test | DG | Altruism | Depleted students | All misreports | More valuable gift | ||
| Mean | 0.499 | 12.82 | 0 | 3.737 | 1.331 | 0.676 | 0.814 | 0.852 | 0.690 | 0.126 | 0.089 | 0.045 |
| SD | 0.500 | 1.432 | 1 | 0.983 | 0.382 | 0.266 | 0.389 | 0.355 | 0.463 | 0.332 | 0.284 | 0.207 |
| Min | 0 | 9.781 | -0.724 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Max | 1 | 16.32 | 3.226 | 5 | 3.375 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| N | 1143 | 1143 | 1106 | 1127 | 1025 | 983 | 983 | 983 | 1143 | 1143 | 1096 | 1046 |
| Missing % | 0 | 0 | 3.24 | 1.4 | 10.32 | 14 | 14 | 14 | 0 | 0 | 0.0885 | 0.045 |
(a) Students’ age refers to their age at the experiment.
(b) Assessed by the following question in the students’ questionnaire: “How many books do you have? You should count the number of books you and your parents possess together. Please do not include your coursebooks and newspapers” (answer categories: less than one shelf 0–50; one shelf ca. 50; 2–3 shelves (ca: 150); 4–6 shelves (ca: 300); 2 bookcases (ca: 300–600 books); 3 bookcases (ca: 600–1000 books); more than 1000 books. The variable was z-standardized to 0 mean and 1 standard deviation.
(c) Grades are integers between 1 (worst) and 5 (best). Grades reported in this table are teacher-awarded grades reported by the teachers. The source of grades is students’ mid-term reporting cards issued in January 2020.
(d) An index was calculated from the mean of the following eight disruptive school behaviors: teasing others, playing or reading something, being noisy, walking around, eating or chewing gum, sending letters, talking or laughing, being late. We asked about the frequency of these behaviors by using the following scale: 1 = “Never”; 2 = “Sometimes”; 3 = “Frequently”; 4 = “Almost always.” We measured this variable in a baseline teacher survey in February 2020, when homeroom teachers answered this question for all students in their class.
(e) DG refers to the delay of gratification. It was measured in a not incentivized, real choice situation where students chose between a more valuable future outcome and a less valuable immediate outcome. Students saw a picture of colorful wristbands and were asked the following question: “Do you want to have one wristband now, or two wristbands tomorrow?” Immediate gratification was coded as 0; delayed gratification was coded as 1. We measured this variable in a baseline online survey in April 2020.
(f) We measured altruism with the following questions: “Imagine that you are going to the zoo with some of your classmates. One of your classmates has forgotten to bring money for the entrance ticket. You have enough money for two entrance tickets. Would you lend your classmate the money for the entrance ticket?” Altruism is binary variable = 1 if the student lent money and 0 otherwise. The category “I do not know” was coded as zero. We measured this variable in a baseline online survey in April 2020.
(g) Missingness is due to the preregistered decision rule that restricted our analysis in the cases where students opted for a more/less valuable gift on their individualized preference list than they rolled.
Fig 1The objects (gifts) used in the dice-roll exercise as incentives.
Fig 2Examples of (mis)reporting the rolled number.
Fig 3Distribution of cheating behavior as a function of treatment with 95% confidence interval.
Results of regression analyses with linear probability models, unstandardized regression coefficients.
| (1) | (2) | (3) | (4) | (5) | (6) | |
|---|---|---|---|---|---|---|
| misreported dice roll | opted for a more valuable object | opted for a less valuable object | ||||
| Control: preregistered | Control: full | Control: preregistered | Control: full | Control: preregistered | Control: full | |
| Treated | 0.044+ (0.024) | 0.045+ (0.024) | 0.044 | 0.045 | 0.002 (0.019) | 0.002 (0.019) |
| Observations | 1,143 | 1,143 | 1,096 | 1,096 | 1,046 | 1,046 |
| R-squared | 0.144 | 0.153 | 0.158 | 0.165 | 0.130 | 0.141 |
| Cohen’s d effect size | 0.132 | 0.135 | 0.155 | 0.160 | 0.010 | 0.009 |
| Mean in the control group | 0.088 | 0.088 | 0.053 | 0.053 | 0.039 | 0.039 |
All models contain constant classroom-fixed effects and the preregistered control variables: gender and age. Standard errors were clustered at the school level.
The list of baseline control variables in full specifications is as follows: gender, age, N of books, GPA, teacher-reported disruptive school behavior, math test, delay of gratification (DG), baseline altruism. Missing values in baseline control variables have been replaced with 0, and separate dummy variables control for missing status. Descriptive statistics and the coding of baseline control variables are shown in Table 1.
Two-sided t-test are used. Robust standard errors in parentheses.
** p<0.01
* p<0.05, + p<0.1.
In Model 3, the significance level of the treatment coefficient is 0.0119. Thus, the coefficient is significant after correcting the significance level for multiple testing since 0.0119 < 0.05/3 [= 0.0167].