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Don’t Tell Me What to Do, Tell Me Who to Follow!

Results indicate that visitors look at the behavior of others in deciding if and how much to donate, but partially reject being told what to do. Also, as the social reference moves farther away from average behavior, its effect on the typical visitor is diminished, leading to lower and less frequent donations.


Wealth and Time Preference in Rural Ethiopia

This study measured the discount rates of 262 farm households in the Ethiopian highlands, using a time preference experiment with real payoffs. In general, the median discount rate was very high and varied systematically with wealth and risk aversion. Our findings, however, warn that rates-of-time preferences (RTPs) and risk aversion reinforce each other and are easily confused. Because the RTPs were so high, what seem like profitable investments from the outside might not seem so from the farmers’ perspectives.


Do Discount Rates Change over Time? Experimental Evidence from Ethiopia

This artefactual experiment in Ethiopia tested the hyperbolic discounting hypothesis by comparing time discounting over cash and consumption goods, using real payoffs. It found no difference in elicited time preferences between cash and consumption goods (tradable or final), which could be the result of missing markets in rural Ethiopia, and there was some evidence of time-inconsistent preferences.


Anonymity, Reciprocity and Conformity: Evidence from Voluntary Contributions to a Natural Park in Costa Rica

In a natural field experiment, the authors quantified the importance of anonymity, reciprocity, and conformity through the provision of social reference levels in order to explain voluntary contributions. In the study setting, the effects of the various treatments were small, suggesting that the self-image as an honorable person, irrespective of other people’s opinions, could be an important explanation of contribution behavior. The experiment overall showed no clear evidence that current practice by charitable organizations is inefficient.


Small-scale Fishermen and Risk Preferences

Using an experimental approach, we investigate the risk preferences of artisanal fishermen in Tanzania waters of Lake Victoria. The experiment concerns pairwise comparisons of hypothetical fishing trips that vary in expected mean and spread of the net revenue.


Smokers’ expectations to quit smoking

We investigate the effectiveness of different smoking policies on smokers’ expectations to quit smoking using a choice experiment on a sample of smokers identified within the World Health Organization (WHO) MONICA Project.


Collective versus Random Fining: An Experimental Study on Controlling Ambient Pollution

This paper presents an experimental study of two different pollution compliance games: collective vis-à-vis random fining as a means to regulate non-point pollution. Result suggests the importance of considering subject pool differences in the evaluation of environmental policies by means of experiments, particularly if those policies involve certain forms of management decisions.


Essays on Environmental Policy-Making in Developing Countries: Applications to Costa Rica

This thesis consists of five papers dealing with fairly heterogeneous issues, based on the problems or topics analyzed, but also based on the methodologies used to approach them. The overriding motives are the design of environmental policies in the context of a typical developing country (where Costa Rica is used as a representative of such countries), and the study and application of techniques that can provide the necessary information for policy-making.