UC Santa Cruz

In Hotelling Revisits the Lab: Equilibration in Continuous and Discrete Time we investigate experimentally the impact of continuous time on a four-player Hotelling location game. The static pure strategy Nash equilibrium (NE) consists of firms paired-up at the first and third quartiles of the linear city. In a repeated simultaneous move (discrete time) treatment, we largely replicate previous findings in which subjects fail to converge to the NE. However, in asynchronous move (continuous time) treatments we see clear convergence towards the NE.

In Stability in Competition? Hotelling in Continuous Time we study Hotelling's classic location duopoly model in continuous time with flow payoffs accumulated over time and the price dimension made explicit. In an experimental setting, subjects chose price and location in treatments varying only by the speed of adjustment. We find that the principle of minimum differentiation generally holds, with little distance between subjects' location decisions. Price decisions, however, tend to be volatile, which is arguably consistent with theory. Our data also support recent literature that the ability to respond quickly increases cooperation.

Aggregate Dynamics in a Large Virtual Economy: Prices and Real Activity in Team Fortress. Virtual economies are growing as internet technology continues to advance. We analyze a large and complete set of transaction data from the Team Fortress 2 virtual economy, which was designed to allow decentralized barter as the sole exchange institution. A small subset of goods emerges endogenously to act as media of exchange. Taking one of these money goods as numeraire, we generate daily prices for thousands of goods. We then generate macroeconomic indicators, including nominal growth and inflation. We find evidence of a particular sort of nominal rigidity related to the circulation of multiple types of currency goods, and also find some localized asset price bubbles associated with announcements by the game designers.