Determinants of Norm Compliance: Moral Similarity and Group Identification

Last registered on November 23, 2021

Pre-Trial

Trial Information

General Information

Title
Determinants of Norm Compliance: Moral Similarity and Group Identification
RCT ID
AEARCTR-0005394
Initial registration date
March 13, 2020

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published
March 13, 2020, 12:41 PM EDT

First published corresponds to when the trial was first made public on the Registry after being reviewed.

Last updated
November 23, 2021, 5:45 AM EST

Last updated is the most recent time when changes to the trial's registration were published.

Locations

Region

Primary Investigator

Affiliation
University of Cologne

Other Primary Investigator(s)

PI Affiliation
University of Michigan

Additional Trial Information

Status
Completed
Start date
2020-03-17
End date
2021-11-22
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
Abstract
What determines whether someone complies with a social norm? The social identity approach offers a mechanism for norm compliance: a person who feels similar to a group identifies more with that group and, in turn, complies with the group's norms. We used an economics experiment to test this mechanism. We manipulated the similarity between an individual and a social group by exogenously changing their similarity in moral values. Moral values were identified using a survey developed in conjunction with moral foundations theory. In one treatment, the subject and social group's moral values were similar, and in another, they were dissimilar. Subsequently, we measured group identification and behavior. To measure behavior, we used a modified rule-following task in which the social group expressed a normative expectation that subjects follow "the rule". We found that moral similarity increased group identification, and group identification increased rule compliance. We show that this behavior change was due to increased group norm sensitivity rather than changes in the group norms. We advance the study of social identity by establishing a causal pathway between group identification and behavior change.
External Link(s)

Registration Citation

Citation
Krupka, Erin and Alexander Schneeberger. 2021. "Determinants of Norm Compliance: Moral Similarity and Group Identification." AEA RCT Registry. November 23. https://doi.org/10.1257/rct.5394
Experimental Details

Interventions

Intervention(s)
We randomly assign participants to one of two treatment conditions. In each treatment, we introduce the participants to the moral position of a different social group. Through this treatment variation, we exogenously alter the moral similarity between our subjects and the social group (high or low moral similarity) and, consequently, the group identification towards the social group.
Intervention Start Date
2020-03-17
Intervention End Date
2020-03-20

Primary Outcomes

Primary Outcomes (end points)
Norm compliance (the number of balls in the blue bucket of the modified rule-following task in the Behavioral Experiment).
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Group identification (the rating of the "Inclusion of Ingroup in the Self Scale" in the Behavioral Experiment).
Secondary Outcomes (explanation)
In our confirmatory analysis, we utilize the distance measure of this scale rather than the overlap measure.

Experimental Design

Experimental Design
The research project includes two surveys and two experiments:

The Pre-Screening Survey: In this survey, participants answer the Moral Foundations Questionnaire (Graham et al., 2011). Based on their responses, we calculate the progressivism index (Clark et al., 2017).

The Rule Elicitation Survey (before the registration): We re-invited ten individuals with a positive progressivism index and ten individuals with a negative progressivism index. In the survey, we asked for a description of the rule from the rule-following task (Kimbrough & Vostroknutov, 2018). Their choices were the "The rule is to put the balls in the blue bucket" or "The rule is to put the balls in the yellow bucket". We used those answers to construct our treatment variation (two social groups that have a distinct moral positions but prescribe the same behavior in the rule-following task).

The Behavioral Experiment: We re-invite participants with a positive progressivism index. In this experiment, we introduce participants to the moral position of either social group, ask for a rating in a continuous version of the "Inclusion of Ingroup in the Self Scale" (Tropp & Wright, 2001) and let them play a modified version of the rule-following task. In this modified version, the rule "The rule is to put the balls in the blue bucket" is replaced by the rule "According to the members of Group A, the rule is to put the balls in the blue bucket".

The Norm Elicitation Experiment: We re-invite participants with a positive progressivism index. In this experiment, we introduce participants to the moral position of either social group and elicit the group norms of individuals with positive progressivism in either treatment of the Behavioral Experiment. Hereby, we utilize the method of Krupka & Weber (2013).
Experimental Design Details
A full description of the experimental design can be found in our pre-analysis plan.
Randomization Method
When subjects participate in either the Behavioral or Norm Elicitation Experiment, the experimental server randomly assigns them to either treatment. To achieve this, we use the Python module NumPy.
Randomization Unit
Individual level
Was the treatment clustered?
No

Experiment Characteristics

Sample size: planned number of clusters
Behavioral Experiment: 2 treatments with 160 participants each.
Norm Elicitation Experiment: 2 treatments with 100 participants each.
Sample size: planned number of observations
Behavioral Experiment: 2 treatments with 160 participants each. Norm Elicitation Experiment: 2 treatments with 100 participants each.
Sample size (or number of clusters) by treatment arms
Behavioral Experiment: 2 treatments with 160 participants each.
Norm Elicitation Experiment: 2 treatments with 100 participants each.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
The sample size in the Behavioral Experiment is based on the following power calculation: We used data from Kimbrough & Vostroknutov (2018) to calculate an expected effect size of 0.3. Subsequently, we used G-Power (Faul, Erdfelder, Lang, & Buchner, 2007) to calculate the minimal required sample size for a one-tailed Wilcoxon-Mann-Whitney test with a parent distribution min ARE, an effect size of 0.3, an alpha-error probability of 0.05, a power of 0.80 and an even allocation between treatments. Based on this power calculation, we require at least 160 subjects per treatment.
IRB

Institutional Review Boards (IRBs)

IRB Name
University of Michigan - Health Sciences and Behavioral Sciences Institutional Review Board
IRB Approval Date
2020-03-02
IRB Approval Number
HUM00163304
Analysis Plan

Analysis Plan Documents

Group Identity Project: Pre-Analysis Plan

MD5: d862f2c60db6b4d08340e3beeab0b96d

SHA1: 7e18aaace61cb3b8b36bd6a4deff02116c59534d

Uploaded At: March 13, 2020

Post-Trial

Post Trial Information

Study Withdrawal

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Request Information

Intervention

Is the intervention completed?
Yes
Intervention Completion Date
November 22, 2021, 12:00 +00:00
Data Collection Complete
Yes
Data Collection Completion Date
March 20, 2020, 12:00 +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
Behavioral Experiment: 2 treatments with 160 participants each.
Norm Elicitation Experiment: 2 treatments with 100 participants each.
Was attrition correlated with treatment status?
No
Final Sample Size: Total Number of Observations
Behavioral Experiment: 2 treatments with 160 participants each.
Norm Elicitation Experiment: 2 treatments with 100 participants each.
Final Sample Size (or Number of Clusters) by Treatment Arms
Behavioral Experiment: 2 treatments with 160 participants each. Norm Elicitation Experiment: 2 treatments with 100 participants each.
Data Publication

Data Publication

Is public data available?
No

Program Files

Program Files
No
Reports, Papers & Other Materials

Relevant Paper(s)

Abstract
What determines whether someone complies with a social norm? The social identity approach offers a mechanism for norm compliance: a person who feels similar to a group identifies more with that group and, in turn, complies with the group's norms. We used an economics experiment to test this mechanism. We manipulated the similarity between an individual and a social group by exogenously changing their similarity in moral values. Moral values were identified using a survey developed in conjunction with moral foundations theory. In one treatment, the subject and social group's moral values were similar, and in another, they were dissimilar. Subsequently, we measured group identification and behavior. To measure behavior, we used a modified rule-following task in which the social group expressed a normative expectation that subjects follow "the rule". We found that moral similarity increased group identification, and group identification increased rule compliance. We show that this behavior change was due to increased group norm sensitivity rather than changes in the group norms. We advance the study of social identity by establishing a causal pathway between group identification and behavior change.
Citation
Schneeberger, Alexander and Krupka, Erin L., Determinants of Norm Compliance: Moral Similarity and Group Identification (November 22, 2021). Available at SSRN: https://ssrn.com/abstract=3969227

Reports & Other Materials