Tomomi Tanaka

Risk and Time Preferences: Linking Experimental and Household Survey Data from Vietnam

We conducted experiments in Vietnamese villages to determine the predictors of risk and time preferences. In villages with higher mean income, people are less loss-averse and more patient. Household income is correlated with patience but not with risk. We expand measurements of risk and time preferences beyond expected utility and exponential discounting, replacing those models with prospect theory and a three-parameter hyperbolic discounting model. Comparable risk parameter estimates have been found for Chinese farmers, using our method.

Risk and Time Preferences: Experimental and Household Survey Data from Vietnam

We conducted experiments in Vietnamese villages to investigate how wealth, political history, occupation, and other demographic variables (taken from a comprehensive earlier household survey) are correlated with risk and time discounting measured in experiments. Experimental results show that in villages with higher mean income, people are less loss-averse and more patient. Villagers in the north who had worked on collective farms and received food from the government on a regular basis are less averse to loss. We expand measurements of risk and time preferences beyond expected utility and exponential discounting, replacing those simple approximations with prospect theory and a three-parameter hyperbolic discounting model.

Resource Allocation with Spatial Externalities: Experiments on Land Consolidation

This paper compares the performance of direct negotiation, double auction, and a two-sided combinatorial call market for consolidating fragmented land. Experimental results suggest direct negotiation produces higher efficiencies than other mechanisms when 1) all commodities need to be traded to achieve efficiency, and 2) subjects are well exposed to various experimental formats. The combinatorial call market performs well when 1) swapping is easily agreeable, and 2) the number of subjects and commodities are increased and the initial endowments are unchallenging. The two-sided combinatorial call market suffers from the holdout problem when the number of subjects and commodities is small.

Price Controls, Non-Price Quality Competition, and the Nonexistence of Competitive Equilibrium

We investigate how price ceilings and floors affect outcomes in continuous time, double auction markets with discrete goods and multiple qualities. When price controls exist, the existence of competitive equilibria is no longer guaranteed; hence, we investigate the nature of non-price competition and how markets might evolve in its presence. We develop a quality competition model based on matching theory. Equilibria of the quality competition model always exist in such price-constrained markets; moreover, they naturally correspond to competitive equilibria when competitive equilibria exist. Additionally, we characterize the set of equilibria of the quality competition model in the presence of price restrictions. In a series of experiments, we find that market outcomes closely conform to the predictions of the model. In particular, price controls induce non-price competition between agents both in theory and in the experimental environment; market behaviors result in allocations close to the predictions of the model.