Research

In the absence of institutions that protect property rights, what conditions allow trade to emerge among self-interested individuals capable of violence? This paper studies a production economy in which individuals can trade peacefully or appropriate goods through conflict. Because conflict, not autarky, is the outside option to trade, peaceful exchange must compete with an alternative that is not equally unattractive to everyone: theft rewards whoever prevails. Trade emerges only when the distribution of economic goods happens to match the distribution of coercive power, and decentralized economic activity provides no mechanism ensuring that alignment.

Organizing into groups could raise returns to specialization in production or coercion, but any division of a group's winnings is itself contested: a member participates only if the group offers more than what she could take by fighting alone. Because coercive power determines each player's claim on cooperative gains, every player has an incentive to expand her own power at the group's expense, undermining the organization specialization would otherwise reward.

A transfer schedule that compensates each player according to her coercive power can, in principle, make peaceful exchange as rewarding as theft. But the existence of such a schedule establishes only the feasibility, not the implementation, of peace: absent an institution to enforce it, each player has an incentive to alter her own coercive power to improve her post-transfer position, unraveling the transfer for the same reason organization unravels. Sustained peace, this paper argues, requires an enforcement mechanism independent of the coercive power it must restrain — a condition decentralized exchange among self-interested individuals cannot supply on its own.

Reviews of daily time-series mortality studies from many cities throughout the world suggest that daily mortality counts are associated with short-term changes in particulate matter (PM) air pollution. One U.S. city, however, with conspicuously weak PM-mortality associations was Salt Lake City, Utah; however, relatively robust PM-mortality associations have been observed in a neighboring metropolitan area (Provo/Orem, Utah). The present study explored this apparent discrepancy by collecting, comparing, and analyzing mortality, pollution, and weather data for all three metropolitan areas on Utah's Wasatch Front region of the Wasatch Mountain Range (Ogden, Salt Lake City, and Provo/Orem) for approximately 10 years (1985-1995). Generalized additive Poisson regression models were used to estimate PM-mortality associations while controlling for seasonality, temperature, humidity, and barometric pressure. Salt Lake City experienced substantially more episodes of high PM that were dominated by windblown dust. When the data were screened to exclude obvious windblown dust episodes and when PM data from multiple monitors were used to construct an estimate of mean exposure for the area, comparable PM-mortality effects were estimated. After screening and by using constructed mean PM [less than/equal to] 10 microm in aerodynamic diameter (PM10) data, the estimated percent change in mortality associated with a 10-mg/m3 increase in PM10 (and 95% confidence intervals) for the three Wasatch Front metropolitan areas equaled approximately 1. 6% (0.3-2.9), 0.8% (0.3-1.3), and 1.0% (0.2-1.8) for the Ogden, Salt Lake City, and Provo/Orem areas, respectively. We conclude that stagnant air pollution episodes with higher concentrations of primary and secondary combustion-source particles were more associated with elevated mortality than windblown dust episodes with relatively higher concentrations of coarse crustal-derived particles.