Maasai Watchman Field Experiment

Last registered on October 24, 2022


Trial Information

General Information

Maasai Watchman Field Experiment
Initial registration date
February 14, 2018

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
February 15, 2018, 11:02 AM EST

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

Last updated
October 24, 2022, 11:36 AM EDT

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


Primary Investigator

University of Toronto

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.
I create randomised variation in farm security by matching randomly selected Kenyan smallholding farmers with subsidized Maasai watchmen to protect farms during the main agricultural season. I explore the effect of theft and property crime by testing whether farmers engage in different types of production when their farms are more secure against theft. I further explore how social networks are used to substitute for imperfect protection of property in an environment where state institutions are unable to fully protect farms, and how theft is used to sanction those who neglect social obligations.
External Link(s)

Registration Citation

Dyer, Julian. 2022. "Maasai Watchman Field Experiment." AEA RCT Registry. October 24.
Former Citation
Dyer, Julian. 2022. "Maasai Watchman Field Experiment." AEA RCT Registry. October 24.
Experimental Details


The intervention in this project is matching farming households to high-quality, trusted Maasai watchmen at a heavily subsidized rate. The intention of this intervention is to cause variation in the security of farms during the long rainy season.
Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
Share of land used for growing high-value or theft-prone crops, and decision to plant new crops.
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
This experiment will consist of a core sample who will be the treatment and control group, answering the main research questions, and a supplementary spillover sample that will be used to estimate the spillovers on crime of the intervention. The core sample will be cluster randomized by village into treatment or control.
Experimental Design Details
See Pre Analysis Plan for details.
Randomization Method
Randomization done in office by computer. See Pre Analysis Plan for details.
Randomization Unit
Village. See Pre Analysis Plan for details.
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
60 Villages, 10 farming households per village.
Sample size: planned number of observations
Target is 600 farming households
Sample size (or number of clusters) by treatment arms
200 farmers treated, 400 control.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
See Pre Analysis Plan.

Institutional Review Boards (IRBs)

IRB Name
University of Toronto Research Ethics Board
IRB Approval Date
IRB Approval Number
Protocol Reference # 34160
Analysis Plan

Analysis Plan Documents

Watchman RCT PAP

MD5: 0c9ab2eee6254602ad254ae119eeab63

SHA1: 4fd58da399dd9c748d37f74cc8fc7bbd6973b35a

Uploaded At: February 18, 2019

Watchman RCT PAP

MD5: 72446025a49708b2b3dcf263b9a3963d

SHA1: c17a555bc8ac864b402baaf8c978c8536719c6e4

Uploaded At: January 23, 2018

PAP - Aug 9 Version

MD5: 89f60123bcda173173ee615594397623

SHA1: 4a32a1137eb575f005a2c57a8a3d117218c9286f

Uploaded At: August 09, 2018

Watchman Field Experiment PAP -- Revised

MD5: d238170d0ca7b16f26d84e72df3e0c8f

SHA1: d7df261cd259d8d665948baf0574d9b91b724d5f

Uploaded At: June 06, 2018

Watchman RCT PAP

MD5: 1a2b111b72ebfc8343e0312a60b8b212

SHA1: a8a1785ee0e2c37038228ff79fb4f894da318fd0

Uploaded At: February 20, 2019


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