Economic Inequality, Subjective Well-being, and American Altruism: An Experimental Investigation

Last registered on July 10, 2023


Trial Information

General Information

Economic Inequality, Subjective Well-being, and American Altruism: An Experimental Investigation
Initial registration date
July 01, 2023

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
July 10, 2023, 9:29 AM EDT

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



Primary Investigator

Illinois Wesleyan University

Other Primary Investigator(s)

Additional Trial Information

Start date
End date
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
This study employs a randomized control experiment featuring a dictator game and a representative participant pool (n=600) to establish the causal effect of information on inequality perception and altruistic behavior. The results show mixed effects of the information intervention on voluntary giving at the aggregate level. A closer investigation reveals that unlike with control subjects, the provision of inequality information encourages treated subjects to give more to an unknown non-profit organization but less to a random stranger, suggesting a stronger degree of institutional trust relative to interpersonal trust. Exposure to inequality statistics is also found to lower subjective well-being among the treatment group. Across multiple quantitative and qualitative belief measures, women generally feel more strongly about income and wealth inequalities and about public policies aimed at inequality reduction than men do. Interesting differences are also documented across political, racial, and other spectra.
External Link(s)

Registration Citation

Nguyen, Hieu. 2023. "Economic Inequality, Subjective Well-being, and American Altruism: An Experimental Investigation." AEA RCT Registry. July 10.
Sponsors & Partners



Experimental Details


Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
Quantitative: average donations in each group.
Qualitative: subjective well-being, overall attitudes toward inequality and public policy targeting inequality reduction, and other outcomes.
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
1. After asking some basic demographic questions, the survey proceeds to elicit all subjects’ beliefs about the current levels of income and wealth inequalities in the US.

2. The subject pool is then split into two groups. The treatment group is informed of the correct answers to all belief-elicitation questions, whereas the control group does not receive this information. "Treated” participants are also asked to reinsert the correct answers before they can proceed.

3. Respondents in both the treated and control groups are then asked several questions about income trends, wealth concentration patterns, public policy, and economic mobility matters.

4. All respondents are given some “house money” (separate from the original show-up fee) and asked to complete two final tasks that simulate a simple dictator game and have direct pecuniary implications.

5. Finally, all subjects are asked to provide a written response to an open-ended question.
Experimental Design Details
Randomization Method
Determined through Prolific's algorithm.
Randomization Unit
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
Sample size: planned number of observations
Sample size (or number of clusters) by treatment arms
301 in control group; 299 in treatment group.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
Only the average total donation in each post-treatment behavioral task was considered for the power calculation. The objective was to see if there was any difference in giving between the treated and control groups. I hypothesized that the average contribution among the control group was 50 points (i.e., one third of the maximum 150 points). Assuming equal standard deviations of 40 points for both groups and a difference in average donations of 10, 15, 20, and 25 between the groups, a two-sample t-test with power 80% and type-1 error rate 5% requires a minimum sample size of 506, 226, 128, and 84, respectively. No other quantitative and qualitative post-treatment outcomes were examined in the power analysis.

Institutional Review Boards (IRBs)

IRB Name
Illinois Wesleyan University's Institutional Review Board
IRB Approval Date
IRB Approval Number


Post Trial Information

Study Withdrawal

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Is the intervention completed?
Intervention Completion Date
September 30, 2022, 12:00 +00:00
Data Collection Complete
Data Collection Completion Date
September 30, 2022, 12:00 +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
600 individuals.
Was attrition correlated with treatment status?
Final Sample Size: Total Number of Observations
600 individuals.
Final Sample Size (or Number of Clusters) by Treatment Arms
301 individuals in control group; 299 individuals in treatment group.
Data Publication

Data Publication

Is public data available?

Program Files

Program Files
Reports, Papers & Other Materials

Relevant Paper(s)

Reports & Other Materials