Abstract
What motivates people to manage natural resources sustainably? Rational choice theory says people are motivated by material rewards, but cultural anthropology and other social and behavioral science literatures have shown that people are motivated by values and norms, which can be eroded by material rewards. The two theoretical stands have come to loggerheads over how to partner with people living close to the natural environment to conserve natural resources. Initially informed by rational choice theory, programs were set up worldwide to pay rural people to conserve natural resources, with payments conditional on households meeting contractual obligations such as not deforesting or polluting water. Some have argued that such payments erode intrinsic motivation to conserve, and that conditionality excludes vulnerable groups—households with small plots, women, the ultra-poor—because they do not have enough land and other resources to set aside for conservation. In theory, removing conditionality in incentive-based conservation programs would increase program participation, particularly attracting more members of vulnerable groups, because it would lower barriers to participation, thus improving the fairness of program outcomes. A clustered randomized controlled trial (RCT) of a Payments for Ecosystem Services (PES) program in rural Bolivia was conducted during 2016-2021 to test this idea. Unexpectedly, rates of participation in the program were similar, on average, in the conditional and unconditional arms of the RCT. The puzzle of why an unconditional treatment did not affect average participation rate motivates this proposal. Our broad objective is to build on theories from cultural anthropology, social psychology, and economics to understand people’s willingness to accept payments for conservation. To do so we used qualitative and quantitative ethnographic methods to gather new data from Bolivia to test hypotheses and explain mechanisms behind unexpected findings from the RCT. The hypotheses center on the role of trust, intrinsic motivation, and perceptions of fair compensation. Our multidisciplinary team was well qualified, having used ethnographic methods in other RCTs in rural Bolivia.
The project was approved as an exempt study by Purdue's Institutional Review Board on September 14, 2023 (IRB-2023_1189). Only adults > 18 yo were included in the study.
The publication includes:
Dataset (in comma-separated and Stata formats) from 163 households in the municipality of Samaipata, Bolivia
Data codebook (in text format)
Data analysis code (in Stata .do format)
Randomized controlled trial procedure and assignment (in text format)
Notes from the workshop on mixed-methods research organized on October 17th, 2025 (in text format)
Presentation delivered by the team at the workshop on October 17th, 2025 (in Microsoft PowerPoint format)