Many important economic and political decisions are made by teams. In the economic literature, however, the decision units are frequently modeled as individual economic agents. The paper experimentally investigates the question to what extent observed team decisions under risk are actually...

Adaptive learning and punishment are highly prominent competing explanations for ultimatum game behavior. We report on an experiment that considers each theory in stand-alone form, so that one does not rely on the other in any substantial way. Our data exhibits patterns for which punishment can...

This paper reports on RatDemo, an example program for the application of RatImage, the Research Assistance Toolbox for computerized human behavior experiments. The complete source code of this short experiment program is listed and briefly discussed. Since RatDemo combines several central...

This paper reports on RatImage, version 3.30. The extended features are presented. RatImage 3.30 is fully downward compatible to the first published version of the Research Assistance Toolbox for Computer-Aided Human Behaivor experiments, RatImage 3.10. This paper is an addendum to the manula of...

If payoffs are tickets for binary lotteries, which involve only two money prizes, then rationality requires expected value maximization in tickets. This payoff scheme was increasingly used to induce risk neutrality in experiments. The experiment presented here involved lottery choice and...

Video taped group decision experiments on a two-person investment game were used to elicit the motivational structure of subjects' behavior. A majority of investors trusted (invested) and a majority of receivers reciprocated (returned). Cognition and decision were focused on extremes: total or...

This paper reports on RatImage, a toolbox specifically developed to simplify the programming of software used in computerized human behavior experiments. RatImage contains Borland Turbo Pascal constans, variables, functions, and procedures which, when used, relieve programmers of many tedious...

In the framework of the classical Black and Scholes model of security market we present the explicit formulas of the minimal hedging portfolios for a number of reward processes of the ``classical'', lookback and Asian type. These results complement the solutions previously received by Mc~Kean,...