Gabriele Camera

Money, credit and banking

We use a modified version of the Lagos-Wright model to introduce an essential role for banks. Due to preference shocks, agents have excess demand for or supply of money balances. Banks arise to reallocate excess cash by taking deposits from sellers and making loans to buyers. We consider two variations of the model: one in which buyers borrow to finance consumption and another in which they borrow to finance investment. We show that for any positive nominal interest rate, the existence of banks leads to a higher level of steady state output and welfare. We also derive conditions under which borrowers voluntarily repay loans. Finally, we examine how monetary injections into the banking system affect the economy. The effects are very similar to limited particiption models and gives rise to a liquidity effect on nominal interest rates

Money and Price Dispersion

We relax restrictions on the storage technology in a prototypical monetary search model to study price dispersion. In this case, buyers and sellers enter matches with potentially different willingness to trade. Across the distribution of possible bilateral matches, prices generally will differ even though agents have identical preferences and technologies. We provide existence conditions for a particularly simple equilibrium pattern of exchange. We prove that in the limiting case where search frictions are eliminated, equilibrium prices are uniform. We also show that a higher initial money stock can raise the average price level and increase price dispersion. Copyright 1999 by Economics Department of the University of Pennsylvania and the Osaka University Institute of Social and Economic Research Association.

Price Dispersion with Directed Search

We present a model that generates empirically plausible price distributions in directed search equilibrium. There are many identical buyers and many identical capacity-constrained sellers who post prices. These prices can be renegotiated to some degree and the outcome depends on the number of buyers who want to purchase the good. In equilibrium all sellers post the same price, demand is randomly distributed, and there is sale price dispersion. Prices and distributions depend on market tightness and on the properties of renegotiation outcomes. In a labor market context, the model generates a strong empirical prediction. If workers can renegotiate the posted wage, then the model predicts a positively skewed and realistic-looking density function of realized wages when the mean number of job-seekers per vacancy is large.

A random matching theory

We develop theoretical underpinnings of pairwise random matching processes. We formalize the mechanics of matching, and study the links between properties of the different processes and trade frictions. A particular emphasis is placed on providing a mapping between matching technologies and informational constraints.

Money and Trust Among Strangers

What makes money essential for the functioning of modern society? Through an experiment, we present evidence for the existence of a relevant behavioral dimension in addition to the standard theoretical arguments. Subjects faced repeated opportunities to help an anonymous counterpart who changed over time. Cooperation required trusting that help given to a stranger today would be returned by a stranger in the future. Cooperation levels declined when going from small to large groups of strangers, even if monitoring and payoffs from cooperation were invariant to group size. We then introduced intrinsically worthless tokens. Tokens endogenously became money: subjects took to reward help with a token and to demand a token in exchange for help. Subjects trusted that strangers would return help for a token. Cooperation levels remained stable as the groups grew larger. In all conditions, full cooperation was possible through a social norm of decentralized enforcement, without using tokens. This turned out to be especially demanding in large groups. Lack of trust among strangers thus made money behaviorally essential. To explain these results, we developed an evolutionary model. When behavior in society is heterogeneous, cooperation collapses without tokens. In contrast, the use of tokens makes cooperation evolutionarily stable.

Cooperative Strategies in Anonymous Economies: An Experiment

We study cooperation in economies of indefinite duration. Participants faced a sequence of prisonerʼs dilemmas with anonymous opponents. We identify and characterize the strategies employed at the individual level. We report that (i) grim trigger does not describe well individual play and there is wide heterogeneity in strategies; (ii) systematic defection does not crowd-out systematic cooperation; (iii) coordination on cooperative strategies does not improve with experience. We discuss alternative methodologies and implications for theory.

The Welfare Cost of Inflation in OECD Countries

The welfare cost of anticipated inflation is quantified in a matching model of money calibrated to 23 different OECD countries for several sample periods. In most economies, in the common period 1978–1998, a representative agent would give up only a fraction of 1% of consumption to avoid 10% inflation. The welfare cost of inflation varies across countries, from a fraction of 0.1% in Japan, to more than 2% in Australia, reaching 6% with bargaining. The model fits money demand data of several countries poorly, however. The fit generally improves with longer sample periods. The results are fairly robust to variations in choice of calibrated parameters and calibration targets.

Communication, commitment, and deception in social dilemmas: experimental evidence

Social norms of cooperation are studied under several forms of communication. In an experiment, strangers could make public statements before playing a prisoner’s dilemma. The interaction was repeated indefinitely, which generated multiple equilibria. Communication could be used as a tool to either signal intentions to coordinate on Pareto-superior outcomes, to deceive others, or to credibly commit to actions. Some forms of communication did not promote the incidence of efficient Nash play, and sometimes reduced it. Surprisingly, cooperation suffered when subjects could publicly commit to actions.

Distributional Aspects of the Divisibility of Money: An Example

I highlight the importance of the distributional aspects of money’s divisibility by comparing a search-theoretic model with random transfers of indivisible money balances, to one with deterministic transfers of partially divisible balances. Randomization allows price flexibility, as if money were fully divisible. Partial divisibility does not, but allows money redistributions. An example of the relevance of such ‘extensive margin’ aspects of divisibility is provided.

An Experiment on Retail Payments Systems

We study the behavioral underpinnings of adopting cash versus electronic payments in retail transactions. A novel theoretical and experimental framework is developed to primarily assess the impact of sellers’ service fees and buyers’ rewards from using electronic payments. Buyers and sellers face a coordination problem, independently choosing a payment method before trading. In the experiment, sellers readily adopt electronic payments but buyers do not. Eliminating service fees or introducing rewards significantly boosts the adoption of electronic payments. Hence, buyers’ incentives play a pivotal role in the diffusion of electronic payments but monetary incentives cannot fully explain their adoption choices. Findings from this experiment complement empirical findings based on surveys and field data.