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Can inequality-reducing income transfers increase cooperation?
Last registered on June 04, 2019


Trial Information
General Information
Can inequality-reducing income transfers increase cooperation?
Initial registration date
May 21, 2019
Last updated
June 04, 2019 12:16 PM EDT

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Primary Investigator
Appalachian State University
Other Primary Investigator(s)
PI Affiliation
Appalachian State University
Additional Trial Information
In development
Start date
End date
Secondary IDs
Income inequality is growing, in the U.S. and around the world. Previous research has shown that high levels of income inequality lead to inefficiencies, thus several countries (e.g., Finland, India, Italy, Netherlands) have begun to implement Universal Basic Income Schemes (UBIs) that transfer incomes to the poor. However, little is understood about how these transfers will impact individuals’ relationships with each other. We investigate if inequality-reducing transfers help to integrate the poor and the rich and enable them to cooperate to enhance community well-being and efficiency. We use laboratory experiments as they allow us to gather clean causal data on alternative policy options at a low cost. In our setting, individuals make monetary contributions to public goods in repeated interactions, which we consider a proxy for decisions such as volunteering, donations, or investments in human capital that generate positive externalities for others.
External Link(s)
Registration Citation
Ramalingam, Abhijit and Brock Stoddard. 2019. "Can inequality-reducing income transfers increase cooperation?." AEA RCT Registry. June 04. https://doi.org/10.1257/rct.4229-1.0.
Former Citation
Ramalingam, Abhijit, Brock Stoddard and Brock Stoddard. 2019. "Can inequality-reducing income transfers increase cooperation?." AEA RCT Registry. June 04. http://www.socialscienceregistry.org/trials/4229/history/47505.
Experimental Details
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
We aim to test whether inequality-reducing income transfers increase voluntary contributions to a public good.
Primary Outcomes (explanation)
Secondary Outcomes
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
We will examine the influence of identity, generations, and communication on the affect of inequality-reducing income transfers. We have three control groups in our repeated public goods games with two parts of 20 decision rounds. In one control group, subjects will have equal endowments in all rounds in each part. In the second control, subjects will experience endowment inequality in all rounds in each part. In the third control, subjects will experience endowment inequality in all rounds of part 1. In part 2, resource endowments will be redistributed such that all subjects will be equally endowed.
With these three control treatments in place, our studies will examine each of these controls with additional treatments factors. In the identity treatment, groups will participate in a group identity task between parts 1 and 2. In the overlapping generations treatments, some of the subjects in a group will "die" (meaning they will leave the experiment) after each part and new subjects will take their place. In the communication treatments, subjects will be able to send chat messages to members of their group or teams.
Experimental Design Details
Not available
Randomization Method
Subjects will register for sessions of the experiment without knowing the treatments ex ante. Once in a session, the computer will randomly assign subjects into groups.
Randomization Unit
The level of randomization is at the group level and the session level.
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
12 independent groups of 4 subjects in each treatment. We plan to run approximately 19 treatments.
Sample size: planned number of observations
912 undergraduate students
Sample size (or number of clusters) by treatment arms
48 undergraduate students per treatment
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB Name
Appalachian State University
IRB Approval Date
IRB Approval Number