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101.
J. A. L. Cranfield 《Revue canadienne d'agroeconomie》2002,50(2):117-133
An optimal advertising rule is derived for a good sold in an open market (beef) when a related substitute good (chicken) is production rationed and whose imports are subject to trade restrictions. Such a rule is developed using a multi-market equilibrium displacement model that reflects demand interrelatedness, open trade of the advertised good (beef), with rationed production and restricted trade of the related good (chicken). The optimal rule nests earlier optimal advertising rules under a variety of conditions. Results underscore the importance of accounting for cross-product advertising effects. When these effects are present (absent), the optimal generic beef advertising intensity in Canada is shown to fall (rise) with elimination of supply management in Canada's chicken sector.
L'auteur dérive une règie sur l'optimisation de la publicité pour un produit vendu sur un marché libre (bœuf) en présence d'un produit de substitution rationné dont on restreint les importations. Pour parvenir à une telle règie, l'auteur a utilisé un modèle de déplacement du point d'équilibre sur un marché multiple illustrant les liens entre la demande des produits concernés, le libre-échange du produit faisant l'objet de la publicité (bœuf) et la restriction de la production et des importations du produit apparenté (poulet). La règie d'optimisation englobe les règles antérieures sur l'optimisation de la publicité dans diverses situations. Les résultats soulignent qu'il est important de prendre en compte les retombées de la publicité sur les autres produits. Au Canada, en présence (absence) de telles retombées, le degré optimal de publicité générique sur le bœuf diminue (augmente) avec l'abolition de la gestion de l'offre de poulet. 相似文献
L'auteur dérive une règie sur l'optimisation de la publicité pour un produit vendu sur un marché libre (bœuf) en présence d'un produit de substitution rationné dont on restreint les importations. Pour parvenir à une telle règie, l'auteur a utilisé un modèle de déplacement du point d'équilibre sur un marché multiple illustrant les liens entre la demande des produits concernés, le libre-échange du produit faisant l'objet de la publicité (bœuf) et la restriction de la production et des importations du produit apparenté (poulet). La règie d'optimisation englobe les règles antérieures sur l'optimisation de la publicité dans diverses situations. Les résultats soulignent qu'il est important de prendre en compte les retombées de la publicité sur les autres produits. Au Canada, en présence (absence) de telles retombées, le degré optimal de publicité générique sur le bœuf diminue (augmente) avec l'abolition de la gestion de l'offre de poulet. 相似文献
102.
103.
The assessment of public universities has gained importance because of the demands from such state government bodies as the executive and the legislature. Public universities are increasingly being asked to account for how efficiently they have used diminishing state financial resources. Administrators thus have the responsibility of ensuring that the university's financial, human, and physical resources are allocated to academic departments in a manner that enhances the institution's efficiency. In this paper, data envelopment analysis (DEA) is proposed for evaluating the efficiency of academic departments at a public university. DEA provides a single measure of efficiency for each academic unit. It also identifies the causes behind the inefficiencies exhibited by poor performing units, as well as the changes that these units need to make in order to improve their efficiencies. Its usefulness as a planning tool is also discussed. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
104.
105.
This paper investigates whether governments can change market structures through interventions. We study the effects of four political events over the life cycle of the market for daily newspapers in the Netherlands. We find that policy measures meant to lower entry barriers in an expanding industry created new entry and increased survival chances for potential entrants and incumbent newspapers. Exit barrier enhancing policies to reduce concentration tendencies have not been successful. 相似文献
106.
Denial of Service (DoS) attacks consist of overwhelming a server, a network or a Web site in order to paralyze its normal activity. The additional parameter in Distributed Denial of Service (DdoS) attacks is the distributing strategy. It means that DDoS attacks do not come from a single computer but stem from all accessible channels and servers. Consequences are multiple, ranging from system errors, temporary inability to access the Web site for normal users to challenging the actual reliability of the Internet. Despite this, Internet users show carelessness. The explanation lies in the specificities of DDoS attacks. We explore possibilities to raise users' awareness about the actual amplitude of problems caused by DDoS attacks. We suggest a careful examination of Internet pricing mechanisms and switching from flat to usage-constraining pricing schemes. 相似文献
107.
The use of transferable discharge permits as a water pollution control policy is rapidly increasing in the United States. Drawing on evidence from existing water quality trading programs, this paper provides a taxonomy of the forms that such markets take. Four main structures are identified: exchanges, bilateral negotiations, clearinghouses, and sole-source offsets. Each of these structures has its own strengths and weaknesses; none is optimal for all scenarios. Since market structure is largely determined by a program's rules, policy makers should be aware of the differences between these structures and the conditions under which each comes to be. 相似文献
108.
Summary. This research studies the role of multivariate distribution structures on random asset returns in determining the optimal
allocation vector for an expected utility maximizer. All our conclusions pertain for the set of risk averters. By carefully
disturbing symmetry in the distribution of the, possibly covarying, returns, we ascertain the ordinal structure of the optimized
allocation vector. Rank order of allocations is also established when a permutation symmetric random vector is mapped into
the returns vector through location and scale shifts. It is shown that increased dispersion in the vectors of location and
scale parameters benefit, ex-ante, investors as does a decrease in the rank correlation coefficient between the location and
scale parameter vectors. Revealed preference comparative static results are identified for the location and scale vectors
of asset returns. For most issues addressed, we arrive at much stronger inferences when a safe asset is available.
Received: August 8, 2000; revised version: January 8, 2001 相似文献
109.
Recently, much of the research into the relation between market values and accounting numbers has used, or at least made reference to, the residual income model (RIM). Two basic types of empirical research have developed. The “historical” type explores the relation between market values and reported accounting numbers, often using the linear dynamics in Ohlson 1995 and Feltham and Ohlson 1995 and 1996. The “forecast” type explores the relation between market value and the present value of the book value of equity, a truncated sequence of residual income forecasts, and an estimate of the terminal value at the truncation date. The analysis in this paper integrates these two approaches. We expand the Feltham and Ohlson 1996 model by including one‐ and two‐period‐ahead residual income forecasts to infer “other” information regarding future revenues from past investments and future growth opportunities. This approach results in a model in which the difference between market value and book value of equity is a function of current residual income, one‐ and two‐period‐ahead residual income, current capital investment, and start‐of‐period operating assets. The existence of both persistence in revenues from current and prior investments and growth in future positive net present value investment opportunities leads us to hypothesize a negative coefficient on the one‐period‐ahead residual income forecast and a positive coefficient on the two‐period‐ahead residual income forecast. Our empirical results strongly support our hypotheses with respect to the forecast coefficients. 相似文献
110.
This paper gives a tree-based method for pricing American options in models where the stock price follows a general exponential Lévy process. A multinomial model for approximating the stock price process, which can be viewed as generalizing the binomial model of Cox, Ross, and Rubinstein (1979) for geometric Brownian motion, is developed. Under mild conditions, it is proved that the stock price process and the prices of American-type options on the stock, calculated from the multinomial model, converge to the corresponding prices under the continuous time Lévy process model. Explicit illustrations are given for the variance gamma model and the normal inverse Gaussian process when the option is an American put, but the procedure is applicable to a much wider class of derivatives including some path-dependent options. Our approach overcomes some practical difficulties that have previously been encountered when the Lévy process has infinite activity. 相似文献