We present an infinite horizon model with capital in which fiat money and barter are two competing means of payment. Fiat money has value because barter is limited by the extent of a double coincidence of wants. The pattern of exchange generally involves both money and barter. We find that the...

It has been previously shown that for sufficiently large pools of patient-donor pairs, (almost) efficient kidney exchange can be achieved by using at most 3-way cycles, i.e. by using cycles among no more than 3 patient-donor pairs. However, as kidney exchange has grown in practice, cycles among...

Colonial Americans complained that gold and silver coins (specie) were chronically scarce. These coins could be acquired only through importation. Given unrestricted trade in specie, market arbitrage should have eliminated chronic scarcity. A model of efficient barter and local inside money is...

We introduce limited liability in a model with a continuum of ex ante identical agents who face aggregate and idiosyncratic income risk. These agents can trade a complete menu of contingent claims, but they cannot commit and shares in a Lucas tree serve as collateral to back up their...

We construct a continuous-time, pure currency economy with the following three key features. First, our modelled economy incorporates idiosyncratic uncertainty—households receive infrequent and random opportunities of lumpy consumption—and displays an endogenous, non-degenerate distribution...

In connection with an earlier paper on the exchange of live donor kidneys (Roth, Sonmez, and Unver 2004) the authors entered into discussions with New England transplant surgeons and their colleagues in the transplant community, aimed at implementing a Kidney Exchange program. In the course of...

Recording industry revenue has fallen sharply in the last three years, and some -- but not all -- observers attribute this to file sharing. We collect new data on albums obtained via purchase and downloading, as well as the consumers' valuations of these albums, among a sample of US college...

For an incompatible patient-donor pair, kidney exchanges often forbid receipt-before-donation (the patient receives a kidney before the donor donates) and donation-before-receipt, causing a double-coincidence-of-wants problem. Our proposed algorithm, the Unpaired kidney exchange algorithm, uses...

Much debate exists around the impact that illegal file sharing may have on the creative industries. Similarly, opinions differ regarding whether the producers of artistic works should be forced to accept any weakening of intellectual property rights resulting from illegal file sharing, or if...

Patients needing kidney transplants may have willing donors who cannot donate to them because of blood or tissue incompatibility. Incompatible patient-donor pairs can exchange donor kidneys with other such pairs. The situation facing such pairs resembles models of the "double coincidence of...