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Safety in Numbers? Free Public Transportation for Women and Women's Safety
Last registered on July 29, 2020


Trial Information
General Information
Safety in Numbers? Free Public Transportation for Women and Women's Safety
Initial registration date
September 02, 2019
Last updated
July 29, 2020 11:53 PM EDT

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Primary Investigator
Harvard University
Other Primary Investigator(s)
PI Affiliation
World Bank
PI Affiliation
Harvard University
Additional Trial Information
In development
Start date
End date
Secondary IDs
In many large cities in developing countries, women are under-represented in public spaces and public transit. This is both caused by and reinforces the risk of experiencing various forms of sexual harassment. We study a policy to make bus travel free for women in Delhi. We compare the policy's effects on women's mobility to free bus travel induced experimentally at the individual level before the policy rollout.
External Link(s)
Registration Citation
Borker, Girija, Gabriel Kreindler and Dev Patel. 2020. "Safety in Numbers? Free Public Transportation for Women and Women's Safety." AEA RCT Registry. July 29. https://doi.org/10.1257/rct.4660-1.3.
Experimental Details
We will provide a random subset of female respondents in our sample with free monthly bus passes on DTC buses and cluster buses until the policy rollout.
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
The key outcome variables of interest in this experiment are bus usage, experienced and perceived safety, and beliefs about bus travel.
Primary Outcomes (explanation)
Secondary Outcomes
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
We will test the partial equilibrium effect of eliminating the financial cost of bus travel and the hassle cost of acquiring a bus pass by randomly providing some female respondents with monthly bus passes. We will compare this to the general equilibrium effects of the Delhi government's policy.
Experimental Design Details
Not available
Randomization Method
Randomization will occur via a computer.
Randomization Unit
The unit of randomization will be the individual woman.
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
800 adult women.
Sample size: planned number of observations
800 adult women, surveyed repeatedly over a period of at most 12 weeks
Sample size (or number of clusters) by treatment arms
400 adult women in the treatment group who receive the free bus pass, 200 women who in the control group who are told they could win a bus pass, and 200 women in the control group who are not considered for the bus pass.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB Name
Harvard University-Area Committee on the Use of Human Subjects
IRB Approval Date
IRB Approval Number
IRB Name
Institute for Financial Management and Research Human Subjects Committee
IRB Approval Date
IRB Approval Number