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

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
September 03, 2019, 4:53 PM EDT

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

Last updated
July 29, 2020, 11:53 PM EDT

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



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.
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
During the baseline survey, we will collect the necessary information to purchase individual bus passes for each respondent. A smaller subsample will also be omitted from this data collection, so we will be able to measure anticipation effects among the control group.
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)

Institutional Review Boards (IRBs)

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


Post Trial Information

Study Withdrawal

There is information in this trial unavailable to the public. Use the button below to request access.

Request Information


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