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111.
112.
Supported by SNF Grant No: DMS 8803556.  相似文献   
113.
This paper incorporates an ecosystem model into a model of a simple economy. The decisionmaking agents in the ecosystem are individual organisms aggregated to the species level. A species may provide utility directly to humans, or it may provide utility indirectly because it is used either as a raw material in goods fabrication or as sustenance for other species. We describe a comparative static equilibrium of the ecosystem where species' demands for other species are equal to the supplies of those other species, and energy is conserved. The ecosystem is then embedded in the economy so that the effects of human intervention can be traced through both the ecosystem and the economy. Human intervention creates ecosystem externalities such that ecosystem equilibria are shifted and the new equilibria affect the utility or the production processes of other humans. This framework allows us to describe in principle which ecosystem services can be efficiently usurped by humans, which waste flows can be efficiently allowed into ecosystems, and which ecosystem organisms and physical attributes can be efficiently maintained.  相似文献   
114.
The Chicago Board Options Exchange concurrently listed European‐style and American‐style options on the Standard and Poor's 500 Index from April 2, 1986 through June 20, 1986. This unique time period allows for a direct measurement of the early exercise premium in American‐style index options. In this study, using ask quotes, we find average early exercise premiums ranging from 5.04 to 5.90% for calls, and from 7.97 to 10.86% for puts. Additionally, we are able to depict a potentially useful functional form of the early exercise premium. As in previous studies, we find some instances of negative early exercise premiums. However, a trading simulation shows that traders must be able to trade within the bid–ask spread to profit from these apparent arbitrage opportunities. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:287–313, 2003  相似文献   
115.
The Internet has increased the level of importance of the end‐consumer market to transportation carriers. In two between subject experiments, carrier disclosure on retail merchant websites is examined as a strategic differentiation strategy. Predictions are offered concerning effects of carrier disclosure strategies on product delivery‐related expectations, consumer attitudes, and intentions to purchase a product online. Results from Study 1 reveal significant differences between disclosure and nondisclosure of the carrier for numerous product delivery‐related variables, as well as many differences between the six carriers examined in this first study. Study 2 extends these findings by showing that providing consumers with a choice of carrier leads to increased levels of satisfaction with the online experience and greater willingness to buy, relative to nondisclosure and disclosure strategies.  相似文献   
116.
This study attempts to infuse relationship marketing theory into the study of logistics outsourcing relationships. In particular, the study demonstrates that not all of the partnerships between customers and providers of third‐party logistics services are the same in terms of their level of development. The existence of distinct levels of partnership established previously in the logistics literature is partially supported and a relationship between level of partnership development and the customer perceptions of key relationship marketing elements and outcomes is established. While exploratory in nature, these findings suggest there are benefits for the increased costs of developing closer partnerships.  相似文献   
117.
This research develops and analyzes a theoretical framework for supplier management and customer relationship strategies, supply chain management strategy, and firm performance using structural equation modeling. Data used in the paper were collected from a comprehensive survey circulated to a wide variety of U.S. and European business executives. Based on the findings, a clearer picture of the practice and benefits of SCM and its strategic implications emerges.  相似文献   
118.
Conditional probability distributions seem to have a bad reputation when it comes to rigorous treatment of conditioning. Technical arguments are published as manipulations of Radon–Nikodym derivatives, although we all secretly perform heuristic calculations using elementary definitions of conditional probabilities. In print, measurability and averaging properties substitute for intuitive ideas about random variables behaving like constants given particular conditioning information.
One way to engage in rigorous, guilt-free manipulation of conditional distributions is to treat them as disintegrating measures—families of probability measures concentrating on the level sets of a conditioning statistic. In this paper we present a little theory and a range of examples—from EM algorithms and the Neyman factorization, through Bayes theory and marginalization paradoxes—to suggest that disintegrations have both intuitive appeal and the rigor needed for many problems in mathematical statistics.  相似文献   
119.
Summary Standard laboratory posted-offer markets respond slowly and incompletely to demand shocks. In these one-sided markets, where sellers control the setting of prices, very little information is transmitted via the process of exchange. For this reason, traders have trouble distinguishing randomness in their own experience from changes in market fundamentals. This paper reports the results of twelve laboratory markets conducted to assess whether some common variants to standard posted-offer rules can correct the adjustment deficiences. Although discounting, multiple postings and excess demand information all improve performance, we find that response remains poor, and efficiencies low.Support for this research was provided by the National Science Foundation (SBR 9319842 and SBR 9320044), and the University of Virginia Bankard Fund. Data are archived at FTP address: fido.econlab.arizona.edu. We wish to thank Charles Plott and Shyam Sunder for useful comments on an earlier draft of this paper. The usual disclaimer applies.  相似文献   
120.
The purpose of this paper is to examine changes in stock return variances following option introduction. The sample consists of National Market System stocks and employs both transaction returns and returns based on bid and ask quotes. Variances are decomposed into portions attributable to bid-ask spreads, return autocorrelations, and intrinsic variances. Spreads play a negligible role in explaining variance changes. A generally positive component to short-term autocorrelations falls following option introduction, increasing variances over short holding periods. Intrinsic variances fall prior to the October 1987 crash, but do not change after the crash with option introduction.  相似文献   
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