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991.
Good estimates place ‘hard core’ smoking rates in the United States at approximately 25%, with little change over the decade of the 1990s. This paper examines the possibilities of ‘harm reduction’ with the use of smokeless tobacco. Specifically, using an econometric model we seek to determine whether an increase in the use of smokeless tobacco would lead to reduced smoking rates in the United States. Applying our model to the NHANES III (National Health and Nutrition Examination Survey) we find that the use of smokeless tobacco by an average U.S. male smoker would increase the average probability of smoke cessation by over 10%. Approximately 3 million additional ‘quits’ would result for 26 million smokers. Our study permits an examination of cessation by age groups and we find that males who use smokeless tobacco between 16 and 65 have a 10–14% probability of quitting but that the probability falls beyond age 66. Important implications for life extension and health costs would attend these results with, under conservative assumptions, life years saved approximating 2.16 million and health care cost-savings of about $3 billion per year.  相似文献   
992.
Probability measures are properly considered subjective, if only as a result of the knowledge limitations of human experience. Even if objective probability can be demonstrated as an unambiguously verifiable property of the physical world, our necessarily imperfect access to such aspects of reality would necessitate the construction of subjective probability measures for examinations of human behavior. This paper will explore the distinction between subjective and purportedly objective probability in principle, and demonstrate that actual probabilities can only be subjective, at least ex ante. The paper will next examine the persistent efforts of philosophers, mathematicians, and particularly quantitatively-inclined social scientists, to construct and employ mistaken conceptions of purportedly objective probability. The neo-indeterminist interpretation of sub-atomic particle physics is addressed next, with its attempt to construct an objective-probabilistic account of reality based on the Heisenberg uncertainty principle. An explanation is suggested for the persistent allure of objective probability in the social sciences, which purports to offer a more economical and parsimonious basis for human behavior and the formation of expectations. The view that there are ontologically privileged, objectively-verifiable probabilities and expectations, will be examined and criticized. It appears to be one source of the discredited, though nonetheless widespread and persistent, belief in the efficacy and feasibility of central economic planning.  相似文献   
993.
Abstract

Conventionally, an advertiser's spending on the creative component of an advertising campaign is small in relation to the media budget and is channeled exclusively to a single advertising agency. Gross challenged those conventions more than 20 years ago, using a mathematical model of advertising effectiveness. His model suggested spending more on the creative component and doing so in a competition among several independent sources. The model assumed a normal distribution of effectiveness of advertisements. Data on response to consumer product ads show that the distribution of effectiveness is not normal, but quite skewed. Using Monté Carlo simulations and Gross's framework, the authors find that the skewness strengthens the case for competition. Shifting a sizable percentage of a campaign budget away from media spending and into competitive generation of creative renderings apparently can be very profitable.  相似文献   
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We study the difference in the volatility dynamics of CBOT corn, soybeans, and oats futures prices across different delivery horizons via a smoothed Bayesian estimator. We find that futures price volatilities in these markets are affected by inventories, time to delivery, and the crop progress period and that there are important differences in the effects across delivery horizons. We also find that price volatility is higher before the harvest starts in most cases compared to the volatility during the planting period. These results have implications for hedging, options pricing, and the setting of margin requirements. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark 30:846–873, 2010  相似文献   
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998.
Differences between yields on comparable‐maturity U.S. Treasury nominal and real debt, the so‐called breakeven inflation (BEI) rates, are widely used indicators of inflation expectations. However, better measures of inflation expectations could be obtained by subtracting inflation risk premiums (IRP) from the BEI rates. We provide such decompositions using an affine arbitrage‐free model of the term structure that captures the pricing of both nominal and real Treasury securities. Our empirical results suggest that long‐term inflation expectations have been well anchored over the past few years, and IRP, although volatile, have been close to zero on average.  相似文献   
999.
This article analyzes the effect of stricter enforcement of the eligibility criteria in the Swedish sickness insurance (SI) system. In 2008, time-restricted assessments of the individual’s working capacity on the 91st and 181st sick day was introduced. Taking advantage of the quasi-experimental feature of the intervention, I find a large and significant increased exit rate around the 181-day assessment. The impact is the result of longer spells outside SI-benefits, indicating that the stricter rules create disincentives to report sick.  相似文献   
1000.
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