Community aspirations and collective action in invasive species management: Evidence from an RCT in Kenya

Last registered on July 19, 2023


Trial Information

General Information

Community aspirations and collective action in invasive species management: Evidence from an RCT in Kenya
Initial registration date
July 11, 2023

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
July 19, 2023, 2:00 PM EDT

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


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

Request Information

Primary Investigator

University of Bonn

Other Primary Investigator(s)

PI Affiliation
University of Bonn
PI Affiliation
Swedish University of Agricultural Sciences
PI Affiliation
University of California

Additional Trial Information

In development
Start date
End date
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
In Kenya, the recent spread of the invasive tree species Prosopis spp. (hereafter referred to as Prosopis) has caused severe adverse impacts, including loss of biodiversity, encroachment of agricultural and pasture lands, depletion of ground and surface water, and significant economic damage. Some uncoordinated attempts have been made to contain the Prosopis invasion, but so far with little success. In 2020, the Kenyan government has decided to develop a National Prosopis Strategy that will provide a well-coordinated, multi-agency approach to control the highly invasive tree Prosopis.
The strategy is aimed at the targeted removal and eradication of Prosopis and replacement with various perennial grasses and trees. Current plans to achieve this goal aim to establish and mobilize different community and village level structures for prevention, early detection, and intervention. Our study experimentally investigates the effects of a video-based intervention with role models for collective action on community aspirations and cooperation in the management of Prosopis. The specific objectives of this study hence are (i) to measure community aspirations using six aspiration dimensions, (ii) to assess individual monetary contributions to the real public good of Prosopis management using a real public goods game, (iii) to investigate whether examples of successful collective action (i.e., a video-based intervention) can influence community aspirations and levels of cooperation, and (iv) to examine whether gender affects levels of cooperation in collective action.
External Link(s)

Registration Citation

Baylis, Kathy et al. 2023. "Community aspirations and collective action in invasive species management: Evidence from an RCT in Kenya." AEA RCT Registry. July 19.
Experimental Details


Our study uses a lab-in-the field experiment as part of the outcome of an RCT to study whether the intervention affects observed behavior in the experiment. The RCT involves a video-based intervention that presents stories of role model villages that have successfully collaborated to address collection action problems (i.e., invasive species management). The design of the real public goods game employs a task directly linked to the management of Prosopis. In a public goods game, individuals choose their individual monetary contributions towards a common good. Specifically, individuals receive an endowment and decide how much of it to contribute to a group account for Prosopis management in their village. In particular, we attempt to test whether community aspirations and cooperation can be altered using a collective action video intervention.
Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
Our primary outcomes of interest are (i) farmers’ cooperation in the real public good of Prosopis management and (ii) farmers’ community aspirations (index). In addition, we are interested in (iii) variations in these outcomes that result from the distinct gender-targeting strategies used in the two treatment arms.
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary outcomes include self-reported contributions, individual aspirations (index), locus of control, self-efficacy, village efficacy, time and risk preferences, a trust index, perceptions about Prosopis, and future-oriented (economic) behavior.
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
The data used in this study will be obtained from four different data collection segments conducted among smallholder farmers in Baringo County, including (i) a collective action video intervention, (ii) a real public goods game experiment, (iii) a community aspirations survey, and (iv) a household survey.
Experimental Design Details
Not available
Randomization Method
Randomization was performed using Stata software.
Randomization Unit
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
Not applicable.
Sample size: planned number of observations
530 farm households
Sample size (or number of clusters) by treatment arms
We employ an RCT with randomization at the household level within each village. 35 villages were randomly selected for the study. In each village, the 15 randomly selected households are randomly assigned to one of three groups (T1, T2, Control) of five households each.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

Institutional Review Boards (IRBs)

IRB Name
ZEF Research Ethics Board, University of Bonn
IRB Approval Date
IRB Approval Number