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Can competition in the hiring market undermine ethnic discrimination during the hiring process?

Last registered on February 21, 2022


Trial Information

General Information

Can competition in the hiring market undermine ethnic discrimination during the hiring process?
Initial registration date
October 27, 2021

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
October 29, 2021, 1:41 PM EDT

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

Last updated
February 21, 2022, 11:48 PM EST

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



Primary Investigator

Queensland University of Technology

Other Primary Investigator(s)

Additional Trial Information

In development
Start date
End date
Secondary IDs
Prior work
This trial is based on or builds upon one or more prior RCTs.
In this experiment, we will experimentally examine the impact of increased competition in the recruitment market on employers' hiring and wage decisions. We design a laboratory experiment where we will use reserve wage to stimulate the hoteling model (Hotelling, 1929) to introduce competition in the hiring market. We will compare 2X2 treatments to identify whether increased competition in hiring market can effectively undermine the ethnic discrimination in both hiring and wage decisions: Hiring competition X flexible wage scheme. In the treatments with hiring competition settings, employers will face hiring competition in the labour market while in the treatments with a flexible wage scheme, employers can choose different wages to increase the likelihood of hiring their preferred candidates. The experiment is designed to test two theories: (1) whether discrimination can help employers to segment the market and escape away from competition; (2) whether ban of wage discrimination will lead to greater hiring discrimination.
External Link(s)

Registration Citation

Hu, Hairong. 2022. "Can competition in the hiring market undermine ethnic discrimination during the hiring process?." AEA RCT Registry. February 21.
Experimental Details



Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
The main variable of interest is the probability of an individual being hired in different treatments, controlled by ethnicity, scores and age. Another main variable is the wage that an individual being offered in different treatments, controlled by ethnicity, scores and age
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary outcome variables are the percentage (%) of minority candidates being hired in different treatments and the differences in mean wage between majority candidates and minority candidates in different treatments.
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
We design a two-stage hiring game where the two participants (i.e. employers) will see four candidates, and they must decide whether to hire them or not in the first stage. If they decide to hire the candidate, they then need to choose a wage for their hired candidate in stage 2. We will introduce an intermediate hiring competition or a flexible wage scheme in the different treatments. To allow for learning effects, the participants will play this two-stage game in 5 independent rounds. The experiment is based on a between-subject design.

In the baseline treatment (Treatment A0), 2 employers will have a hiring competition if both employers decide to hire the same candidate, and they are free to choose different wage offer to different candidates. As the main experimental variation (Treatment B0), we consider a non-competitive treatment where employers are free to choose different wage offers and always hire the preferred candidate without competition.

In the main treatments, 2 employers are unable to practice wage discrimination, and they can only choose identical wages for all the preferred candidates under competitive (Treatment A1) and non-competitive scenarios (Treatment B1).

The experiment is designed to examine the economic theory which predicts that discrimination can be profitable for employers to segment market and reduce wage payments in the presence of hiring competition (as in Treatment A0), and it is not profitable in the absence of hiring competition (as in Treatment B0). Moreover, the hiring discrimination against minority workers should be greater if wage discrimination is feasible (as in Treatment A0) than if wage discrimination is banned (as in Treatment A1). And such differences should only exist in the competitive environment (A0-A1) and do not exist in the non-competitive environment (B0-B1).
Experimental Design Details
Randomization Method
randomised by a computer
Randomization Unit
individual employee candidate
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
Each treatment has 100 sessions. So there will be 400 sessions
Sample size: planned number of observations
Each session has 4 employee candidates and 2 participants. The total observations are 4x2x4x100 = 3200 observations
Sample size (or number of clusters) by treatment arms
400 sessions
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

Institutional Review Boards (IRBs)

IRB Name
IRB Approval Date
IRB Approval Number
Analysis Plan

Analysis Plan Documents

Analysis plan

MD5: 0486c7179d93ab6cb7d2411dc1d98161

SHA1: 86da1ed8e3035b551e0acaea4006f38d6ee561cd

Uploaded At: February 21, 2022


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Is the intervention completed?
Data Collection Complete
Data Publication

Data Publication

Is public data available?

Program Files

Program Files
Reports, Papers & Other Materials

Relevant Paper(s)

Reports & Other Materials