Bringing the Lab to the Field: More than Changing Subjects

This paper discusses why running experiments in the field, outside of the university lab, can help us enrich the analysis we do of experimental data. One of the main arguments of the paper is that people participating in experiments, including students, do not come naked to the lab. They bring a great deal of rules of thumb, heuristics, values, prejudices, expectations and knowledge about the others participating, and about similar games, and use such information to make their decisions. The paper offers a short mention of relevant field experiments, and a more detailed look at field experiments conducted by the author, including a data set of CPR experiments run in 10 villages, between 2000 and 2002, with more than 1300 villagers in about 220 sessions, and replications with about 250 university students in more than 40 sessions. It offers then main lessons from bringing the lab to the field. Also there is a discussion of additional information gathered through different field instruments as well as community workshops with the participants to discuss the experimental data, the external validity of the experiments and their results, through parallels with their daily life. One of the lessons is that the greater variance in certain demographics about the experimental subjects might help explain variations in lab behavior that cannot be fully explained by the experimental institutions we study. Also, certain significant differences in behavior between villagers and students will be discussed.

Evolutionary game theory: Temporal and spatial effects beyond replicator dynamics

Evolutionary game dynamics is one of the most fruitful frameworks for studying evolution in different disciplines, from Biology to Economics. Within this context, the approach of choice for many researchers is the so-called replicator equation, that describes mathematically the idea that those individuals performing better have more offspring and thus their frequency in the population grows. While very many interesting results have been obtained with this equation in the three decades elapsed since it was first proposed, it is important to realize the limits of its applicability. One particularly relevant issue in this respect is that of non-mean-field effects, that may arise from temporal fluctuations or from spatial correlations, both neglected in the replicator equation. This review discusses these temporal and spatial effects focusing on the non-trivial modifications they induce when compared to the outcome of replicator dynamics. Alongside this question, the hypothesis of linearity and its relation to the choice of the rule for strategy update is also analyzed. The discussion is presented in terms of the emergence of cooperation, as one of the current key problems in Biology and in other disciplines.Comment: Review, 48 pages, 26 figure

Viable tax constitutions

Taxation is only sustainable if the general public complies with it. This observation is uncontroversial with tax practitioners but has been ignored by the public finance tradition, which has interpreted tax constitutions as binding contracts by which the power to tax is irretrievably conferred by individuals to government, which can then levy any tax it chooses. However, in the absence of an outside party enforcing contracts between members of a group, no arrangement within groups can be considered to be a binding contract, and therefore the power of tax must be sanctioned by individuals on an ongoing basis. In this paper we offer, for the first time, a theoretical analysis of this fundamental compliance problem associated with taxation, obtaining predictions that in some cases point to a re-interptretation of the theoretical constructions of the public finance tradition while in others call them into question

An Intergenerational Common Pool Resource Experiment

intergenerational common pool resources;growth and altruism;free-riding intentions