We compare two different elicitation methods for measuring risk attitudes on a sample of French farmers. We consider the lottery tasks initially proposed by Holt and Laury (Econ Rev 92:1644–1655, 2002) and by Eckel and Grossman (Evol Hum Behav 23:281–295, 2002; J Econ Behav Org 68:1–7, 2008). The main empirical result from this within-subject study is that risk preference measures are affected by the type of mechanism used. We first show that this risk preference instability can be related to non-expected (...) utility preferences of farmers. Using a risk-taking psychometric questionnaire, we then demonstrate that risk preferences of farmers are context-dependent. This may be another explanation of the observed risk preference instability. (shrink)

Most decision-making research in economics focuses on individual decisions. Yet, we know, from psychological research in particular, that individual preferences can be sensitive to social pressures. In this paper, we study the impact of a group environment on individual preferences for risky and ambiguous prospects. In our experiment, each participant was invited to make a series of lottery-choice decisions in two different conditions. In the Alone condition, individuals made private choices, whereas in the Group condition, individuals belonged to a three-person (...) group and group members’ choices were aggregated according to either a majority or unanimity rule. This design allows us to study the impact of a group environment on individuals’ attitude towards both risky and ambiguous prospects, while controlling for the decision rule used in the group. Our experimental results show that when individuals are in the Group condition, they tend to be less risk averse and more ambiguity averse than when they are not part of a group. Our experiment also suggests that the decision rule matters as it shows that these two trends tend to be stronger when the group implements a unanimity rule. Specifically, we found that individuals who belong to a group implementing a unanimity rule are significantly less risk averse than individuals who belong to a group that relies on the majority rule. We obtained a similar—but non-significant—result under ambiguity. (shrink)

This article addresses the value of information that affects the ambiguity faced by a decision maker. Our analysis is applied to the case of a farmer whose production can be damaged by a pest attack with unknown probability, this damage being reduced if the farmer decides to use a pesticide. Early warning systems have precisely been implemented in many countries to help farmers avoid inappropriate decisions in terms of pesticide use. We investigate, both theoretically and experimentally, how farmers value these (...) systems. We propose a two-state self-insurance model in which an α\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\alpha$$\end{document}-MaxMin Expected Utility farmer may use pesticides that reduce the loss in the accident state while incurring a cost in both states. Her decision to self-insure or not depends on risk and ambiguity attitudes. We compile and compare the value of two types of information leading to a reduction of ambiguity and analyze their properties with respect to ambiguity attitude. Both types of information are valued positively if the farmer is ambiguity averse. We conduct a framed field experiment in which farmers and agricultural students have to decide whether or not to apply pesticides depending on risk, ambiguity and the associated monetary gains resulting from pesticide cost. The experimental findings support the theory. The average value of information among all participants is between €0.9/ha and €3.3/ha depending on the information gain. (shrink)

Cet article aborde les formes de contrôle des biens communs par des entreprises commerciales en étudiant le cas des logiciels libres. Les logiciels libres sont des logiciels dont le code source est librement accessible, et peut être modifié et partagé. Cette éthique de partage a permis l’émergence d’un modèle collaboratif souvent présenté comme l’exemple type des « communs numériques ». Cependant, de plus en plus d’entreprises participent aujourd’hui au développement des logiciels libres. Si plusieurs analystes voient d’un bon œil cette (...) contribution commerciale, d’autres font ressortir les formes de contrôle que ces entreprises mettent en place pour tirer profit des communs en logiciels libres. En recensant différentes études sur ces questions et en analysant plus précisément les cas de Symfony et de Redhat, deux logiciels libres fortement développés par des entreprises commerciales, le présent article s’attarde sur ces formes de contrôle des communs numériques et en fait ressortir les conséquences éthiques. (shrink)

This article deals with the impact of governmental assistance on insurance demand under ambiguity, i.e., in situations where probabilities are uncertain. First, using a model of insurance demand under ambiguity, we derive theoretical predictions about the impact of several governmental assistance programmes on optimal insurance demand. For example, governmental assistance through a fixed public support scheme implies that partial insurance is always optimal under fair insurance with ambiguity. Second, we present the results of an experiment designed to test these predictions. (...) We find support for several of our theoretical predictions. For example, the presence of governmental assistance through a fixed public support scheme decreases individuals’ willingness to pay to be fully insured. Finally, we compare these results with those obtained for a risk situation. We find that, regardless of the form of governmental assistance, participants in the ambiguity context are consistently willing to pay more to be fully insured than participants in the risk situation. (shrink)