Macroeconomists have for some time been aware that the New Keynesian Phillips curve, though highly popular in the literature, cannot explain the persistence observed in actual inflation. We argue that one of the more prominent alternative formulations, the Fuhrer and Moore (1995) relative contracting model, is highly problematic. Fuhrer and Moore's 1995 formulation generates inflation persistence, but this is a consequence of their assuming that workers care about the past real wages of other workers. Making the more reasonable assumption that workers care about the current real wages of other workers, one obtains the standard formulation with no inflation persistence.
Creating the U.S. Dollar Currency Union, 1748-1811: A Quest for Monetary Stability or a Usurpation of State Sovereignty for Personal Gain? by Farley Grubb. Published in volume 93, issue 5, pages 1778-1798 of American Economic Review, December 2003
We develop a conceptual framework for valuing biodiversity from an economic perspective. We argue for a dynamic economic welfare measure of biodiversity that complements the literature on benefit-cost approaches and genetic distance/phylogenic tree approaches. Using a unified model of optimal economic management of an ecosystem under ecological and genetic constraints, we identify gains from management policies leading to a more diverse system, using the Bellman state valuation function of the problem. We show that a more diverse system could attain a higher value although the genetic distance of the species in the more diverse system could be almost zero.
At least 41 million Americans are currently without health insurance in any given month (U.S. Bureau of the Census, 2002). They are uninsured for a variety of reasons, and most people who lack coverage are affected by more than one reason. Two generalizations can be made, however. First, a majority simply cannot afford to purchase health insurance unless it is heavily subsidized. Most do not have access to employer-sponsored coverage and so must purchase any insurance in the non-group (individual) health-insurance market - a market where, as I explain below, insurance is typically twice as expensive as employer-group coverage if it is not denied outright. Since about two-thirds of the uninsured have incomes below $35, 000, non-group health-insurance premiums often exceed 10 percent of their incomes. The second generalization is that, to an important extent, high premiums in the non-group market and denial of coverage reflect market failure due to asymmetric information. Insurers can never know as much as an individual does about his or her health, family history of health problems, and tendency to seek medical care. Because of this asymmetry, it is impossible for an insurer to set premiums that accurately reflect the non-random portion of health-care costs for different individuals. The non-group market is the only health-insurance option for people without employersponsored coverage. Tax-related subsidies as proposed by members of Congress and the Bush administration do not address the market-failure problems and so are unlikely to make insurance much more affordable. To increase access to health insurance, risk in the non-group market needs to be shifted to a broader population base. In what follows, I first describe the three distinct health-insurance markets in which people can obtain health insurance, and the special nature of competition among insurance companies in the non-group market. Then I make the case for government to act as reinsurer and assume the risk of extremely high-cost people. Efficiency in the non-group health-insurance market would be improved if the government reinsured the market. Equity also would be increased if the government acted as reinsurer because more uninsured people would have access to insurance. Finally, I describe precedents for this role for government in other markets, and why tax-related subsidies will not succeed in increasing health-insurance coverage unless the risks of extremely high costs are shifted to the government.
In many empirical studies of the effect of social programs researchers assume that, conditional on a set of observed covariates, assignment to the treatment is exogenous or unconfounded (aka selection on observables). Often this assumption is not realistic, and researchers are concerned about the robustness of their results to departures from it. One approach (e.g., Charles Manski, 1990) is to entirely drop the exogeneity assumption and investigate what can be learned about treatment effects without it. With unbounded outcomes, and in the absence of alternative identifying assumptions, there are no restrictions on the set of possible values for average treatment effects. This does not mean, however, that all evaluations are equally sensitive to departures from the exogeneity assumption. In this paper I explore an alternative approach, developed by Paul Rosenbaum and Donald Rubin (1983), where the assumption of exogeneity is explicitly relaxed by allowing for a limited amount of correlation between treatment and unobserved components of the outcomes. The starting point of the sensitivity analysis is the assumption that the exogeneity assumption is satisfied only conditional on an additional unobserved covariate. Making assumptions about the effect of the unobserved covariate on the outcome and its correlation with the treatment, I trace out the set of possible values for the treatment effect of interest. By considering a sufficiently large set of possible correlations with outcomes and treatment, one can recover the bounds on the treatment effect derived by Manski (1990). The approach here, in the spirit of Rosenbaum and Rubin (1983) and Rosenbaum (1995), is to allow only a limited amount of correlation and to judge the sensitivity of average treatment-effect estimates to such correlations. There are two novel features of the proposed analysis. First, rather than formulate the sensitivity in terms of coefficients on the unobserved covariate, the sensitivity results are presented in terms of partial R values, which may be easier to interpret. Second, the partial R values of the unobserved covariates are compared to those for the observed covariates in order to facilitate judgments regarding the plausibility of values necessary to substantially change results obtained under exogeneity. The proposed sensitivity analysis is conceptually related to the practice of assessing sensitivity of estimates by comparisons with results obtained by discarding one or more observed covariates (James Heckman and V. Joseph Hotz, 1989; Rajeev Dehejia and Sadek Wahba, 1999; Jeffrey Smith and Petra Todd, 2001). The attraction of the sensitivity analysis is that it is more directly relevant: one is not interested in what would have happened in the absence of covariates actually observed, but in biases that are the result from not observing all relevant covariates.
A Picture Is Worth a Thousand Symbols: A Sociologist's View of the Economic Pursuit of Truth by Joel M. Podolny. Published in volume 93, issue 2, pages 169-174 of American Economic Review, May 2003
Physical telecom networks are costly and few, traditionally to the point of monopoly. Innovation thrives with many independent minds. So one might hope independent innovators, not only its proprietor M, can offer innovative services on a network, as has been true on the Internet. This issue is central in telecom policy; it also arises elsewhere, including complaints about Microsoft. I try to expound the following key points. Often an unregulated M has ex ante incentives to organize service innovation efficiently. But this incentive breaks down ex post as M can extract an independent J’s quasi-rents (Farrell and Michael Katz 2000). Even ex ante, the one monopoly rent theorem (Ward Bowman 1957) fails when M’s bottleneck access business is more regulated than its competitive services (e.g., Jean-Jacques Laffont and Jean Tirole 2000). This tempts M to sabotage J’s innovations. Quarantining M from the service sector solves these problems, but excludes the firm with (often) the best opportunities and the strongest incentives to innovate. Parity pricing or ECPR (Robert Willig 1979) purports to get the best of both worlds (BoBW). But it seems so hard to implement in innovation markets that one might construe ECPR analysis as reductio ad absurdum for BoBW.
Equity market liberalizations are like IPOs, but they are IPOs of a country's stock market rather than of individual firms. Both are endogenous events whose benefits are limited by poor investor protection, agency costs, and information asymmetries. As for stock prices following an IPO, there are legitimate concerns about the efficiency in the period following the liberalization of the stock market returns of countries that liberalize their equity markets. Equity markets of liberalizing countries experience extremely strong performance immediately after the liberalization, but then go through a period of poor performance. This pattern of stock returns is more dramatic for countries with poorer financial development before the liberalization.
The Carrot or the Stick: Rewards, Punishments, and Cooperation by James Andreoni, William Harbaugh and Lise Vesterlund. Published in volume 93, issue 3, pages 893-902 of American Economic Review, June 2003