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Social Identity and Incentives in Workgroups
Last registered on June 12, 2020


Trial Information
General Information
Social Identity and Incentives in Workgroups
Initial registration date
March 31, 2017
Last updated
June 12, 2020 6:18 AM EDT
Primary Investigator
Nanyang Technological University
Other Primary Investigator(s)
Additional Trial Information
Start date
End date
Secondary IDs
The project focuses on the effects of social identity in combination with different economic incentives on outcomes like effort, cooperation and overall productivity. In particular, it aims to test whether common social identity in teams/ work-groups affects the relative effectiveness of cooperative versus competitive based incentives. In addition, we aim to explore the mechanisms by which this arises: e.g. more salient other-regarding social norms/moral preferences.
External Link(s)
Registration Citation
Yeo, Jonathan. 2020. "Social Identity and Incentives in Workgroups." AEA RCT Registry. June 12. https://doi.org/10.1257/rct.2139-10.299999999999999.
Former Citation
Yeo, Jonathan. 2020. "Social Identity and Incentives in Workgroups." AEA RCT Registry. June 12. http://www.socialscienceregistry.org/trials/2139/history/70323.
Experimental Details
The study will consist of a laboratory experiment of which participants are recruited from the University's behavioural research platform.
They will be paid for turning up as well as their performance in a real effort task. Overall, we have a 2 X 2 treatment design.
Participants will be assigned a group identity according to their relative preferences over 5 pairs of Klee and Kandinsky paintings, with salience increased via a discussion on the artist of the 6th painting. They will then be assigned to teams which are either heterogeneous or homogeneous in group identity. Each team will then be randomly subject to a tournament or team incentive scheme where they complete a real effort task with some cooperative possibility.
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
The key outcomes variables are effort, cooperation and overall productivity.
Primary Outcomes (explanation)
Effort will be calculated by looking at the time taken to complete each unit of the effort task. Cooperation will be examined by looking at the proportion whom choose to help others during the task. Productivity is calculated by looking at the final scores in the real effort task.
Secondary Outcomes
Secondary Outcomes (end points)
Secondary outcome variables: 1) measurements of participants' moral and social norms regarding cooperation. 2) Type of helper they are in the experiment.
Secondary Outcomes (explanation)
1) Moral and social norms will be constructed via factor analysis on several survey questions administered. 2) Their classification into types of helpers will be obtained from a survey question which asks them about how they would respond to others on their team cooperating.
Experimental Design
Experimental Design
The experimental design consists of two parts. The first part consists of assigning group identity among participants and making it salient. The second part consists of a real-effort task in teams which have different compositions of participants from the groups. There will be an element of cooperation in the real-effort task. Teams will be assigned a random incentive structure: a tournament or team scheme.
All participants are then required to fill in a post-experiment questionnaire.
Experimental Design Details
Part 1: Firstly, participants are seated randomly in the lab for each session. In the first part, they are asked their preferences over 5 pairs of Klee and Kandinsky Paintings sequentially. Their preferences relative to others in the same session determine their group assignment. They then have a task to increase their group identity salience which involves discussing whom is the artist of a final pair of Klee vs Kandinsky paintings with members of their assigned group. They then answer the question individually after the discussion, and are only paid an incentive if a majority of their assigned group gets the answer correct. Part 2: Participants are then assigned into 6-person teams which can either be (maximally) heterogeneous or homogeneous. They then have to complete several rounds of a real-effort task which involves sets of decoding problems. There are 2 kinds of question sets: easy and difficult, with the latter involving a greater number of questions in the set. An element of cooperation is built into the task by allowing for help requests when facing a difficult question set. Help requests are sent automatically on behalf of the participant whom faces a difficult question set. Decisions to help must be made at the beginning of the round. Providing help reduces the difficulty (number of questions) in the question set of the requester, but increases that of the helper, with help being efficient. They are also given the chance to rest during the task, and are given a small incentive for taking short breaks in between sets of questions. Teams are then assigned a random incentive structure: team or tournament and they will play under this scheme for several rounds. Team incentives involve output sharing while tournament incentives have rank-based piece rates. Participants are only informed of their payment at the end of the experiment, after completing an online post-experiment questionnaire.
Randomization Method
Randomization into different treatment groups by software.
Randomization Unit
Participants are randomised into homogeneous or heterogeneous workgroups. Subsequently, workgroups are randomised into tournament or team pay.
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
>=48 workgroups, 6 participants in each workgroup
Sample size: planned number of observations
>=288 participants
Sample size (or number of clusters) by treatment arms
>=12 workgroups in homogeneous teams, tournament incentives
>=12 workgroups in homogeneous teams, team incentives
>=12 workgroups in heterogeneous teams, tournament incentives
>=12 workgroups in heterogeneous teams, team incentives
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB Name
IRB Approval Date
IRB Approval Number
Post Trial Information
Study Withdrawal
Is the intervention completed?
Intervention Completion Date
December 01, 2018, 12:00 AM +00:00
Is data collection complete?
Data Collection Completion Date
December 01, 2018, 12:00 AM +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
48 workgroups
Was attrition correlated with treatment status?
Final Sample Size: Total Number of Observations
288 participants
Final Sample Size (or Number of Clusters) by Treatment Arms
12 workgroups in homogenous, tournament. 12 workgroups in heterogenous, tournament, 12 workgroups on homogeneous, team pay, 12 workgroups in heterogenous, team pay.
Data Publication
Data Publication
Is public data available?
Program Files
Program Files
Reports, Papers & Other Materials
Relevant Paper(s)