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Maasai Watchman Field Experiment
Last registered on November 03, 2019


Trial Information
General Information
Maasai Watchman Field Experiment
Initial registration date
February 14, 2018
Last updated
November 03, 2019 10:55 AM EST
Primary Investigator
University of Toronto
Other Primary Investigator(s)
Additional Trial Information
On going
Start date
End date
Secondary IDs
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. 2019. "Maasai Watchman Field Experiment." AEA RCT Registry. November 03. https://doi.org/10.1257/rct.2692-13.1.
Former Citation
Dyer, Julian. 2019. "Maasai Watchman Field Experiment." AEA RCT Registry. November 03. http://www.socialscienceregistry.org/trials/2692/history/56388.
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
Not available
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.
IRB Name
University of Toronto Research Ethics Board
IRB Approval Date
IRB Approval Number
Protocol Reference # 34160
Analysis Plan

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