Siegfried K. Berninghaus

Voluntary contributing in a neighborhood public good game: An experimental study

In repeated Public Good Games contributions might be influenced by different motives. The variety of motives for deciding between (more or less) free-riding probably explains the seemingly endless tradition of theoretical and experimental studies of repeated Public Good Games. To more clearly distinguish the motives, we try to enrich the choice set by allowing players not only to contribute but also to locate their contribution to one of the player positions. The location choice affects what individual players gain, but not the overall efficiency of contributing, and allows for discrimination, e.g., rewarding and sanctioning co-players differently. Our experimental results show that adding location choice promotes voluntary cooperation, although discrimination itself has no signifficant effect on behavior.

Buying Versus Hiring: An Indirect Evolutionary Approach

On a symmetric homogeneous oligopoly market with stochastic demand, firms can either hire employees or buy their labor input on a competitive labor market. Whereas the wage of hired labor does not depend on the realization of stochastic demand, the price of ‘bought’ labor reacts positively to product demand. We derive the equilibrium price vector to define an evolutionary process, assuming that the number of hiring firms increases when they earn more than buying firms. We then derive and discuss the stationary distribution of this stochastic adaptation process.

Reciprocity in Locating Contributions: Experiments on the Neighborhood Public Good Game

In repeated public good experiments, reciprocity helps to sustain high levels of cooperation. Can this be achieved by location choices in addition to making contributions? It is more realistic to rely on an intuitive neighborhood model for community members who interact repeatedly. In our experiments, participants can locate their contribution, yielding a small benefit for the participant, who receives the contribution and a small disadvantage for the participant, at the opposite location. This mechanism of individually targeted sanctions helps to foster initial cooperation. It decreases over time, however. Location choices are used to reciprocate, but may not suffice to stabilize voluntary cooperation as an effect observed in the field.

Approximate truth of perfectness: An experimental test

Approximate truth refers to the principle that border cases should be analyzed by solving generic cases and solving border cases as limits of generic ones (Brennan et al., 2008). Our study experimentally explores whether this conceptual principle is also behaviorally appealing. To do so, we focus on perfectness (Selten, 1975) and use his example game with (no) multiplicity of (perfect) equilibria. Distinguishing three uniform perturbation levels, we check for monotonicity (all players react monotonically to the perturbation level) and then explore the behavioral relevance of approximate truth.

How competition in investing, hiring, and selling affects (un)employment

Most models of labor markets and (un)employment neglect how competition among firms or sectors of the economy affects their hiring of workers and working times. Our approach pays special attention to such effects by proposing a complex stage game where firms invest in capital equipment before hiring workers. Working times are adjusted to demand which is implied by price competition. A special advantage of such a framework is that one can distinguish two kinds of employment effects, namely the numbers of workers as well as their working times, and that one can locate which firm or sector suffers from unemployment. Instead of solving the model in full generality we offer several equilibrium scenarios showing that certain economic phenomena are consistent with subgame perfect equilibrium behavior.