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961.
Affinity card programs have become popular in recent times and account for one fifth of all credit card accounts. There is no research that links affinity card programs to customer profitability. Moreover, little is known about what type of affinity card programs would lead to higher profit. Using a large proprietary dataset we answer the above questions. We also apply propensity score matching, a relatively new technique, to control for selection bias in addressing the above issues. Contrary to previous research and common belief, we show that affinity card customers are no more profitable than non-affinity card holders. We also show that sports-based affinity programs are the least profitable and surprisingly, alumni-based affinity programs also do poorly relative to other types of affinity. On the positive side, affinity card customers are lower risk and help to lower the average risk of the portfolio of customers. 相似文献
962.
Permit markets are celebrated as a policy instrument since they allow (i) firms to equalize marginal costs through trade and (ii) the regulator to distribute the burden in a politically desirable way. These two concerns, however, may conflict in a dynamic setting. Anticipating the regulator's future desire to give more permits to firms that appear to need them, firms purchase permits to signal their need. This raises the price above marginal costs and the market becomes inefficient. If the social cost of pollution is high and the government intervenes frequently in the market, the distortions are greater than the gains from trade and non-tradable permits are better. The analysis helps to understand permit markets and how they should be designed. 相似文献
963.
Despite the passage of several decades since the revolution of 1989, there is little professional literature designed to prepare foreign investors for the Romanian business culture. Visitors to this nation discover a friendly people who engage in business practices often characterized as perplexing, frustrating, and imbued with self-defeating actions. The communist period in Romania's history imbedded unethical behavior into the nation's culture, including the morally ambiguous practice of favor trading. This paper describes this central business activity and how it shapes business dealings and often undermines opportunities. The cultural context that created the favor trading environment is discussed, and methods for managing this perplexing practice are explained. 相似文献
964.
Molly K. Reif Jennifer M. Wozencraft Lauren M. Dunkin Charlene S. Sylvester Christopher L. Macon 《Journal of Great Lakes research》2013
The U.S. Army Corps of Engineers (USACE) Joint Airborne Lidar Bathymetry Technical Center of Expertise (JALBTCX) collected its first airborne coastal mapping data on the Great Lakes in 1995. Since then, the JALBTCX has collected nearly 5 billion elevation and depth measurements and created over 2000 geographic information system (GIS) products for the shorelines of the Great Lakes. With improvements in airborne coastal mapping technology and the introduction of regional management for the USACE, surveys expanded into the regional scale, multi-sensor National Coastal Mapping Program (NCMP). The NCMP was initiated in 2004 to produce recurrent, regional, high-resolution light detection and ranging (lidar) elevation data and hyperspectral and aerial imagery to support regional sediment management, regulatory functions, flood damage reduction, asset management, emergency operations, and environmental stewardship. The JALBTCX is a collaboration among the USACE, the U.S. Naval Oceanographic Office (NAVOCEANO), and the National Oceanic and Atmospheric Administration (NOAA). The partners have worked together on airborne coastal mapping and charting since the late 1980s with the goal of advancing airborne lidar bathymetry and associated technologies. The collaboration has fielded three generations of airborne sensors and has transferred this technology to the commercial sector, supporting an expanding market for bathymetric lidar. The purpose of this paper is to provide an overview of the history of USACE survey efforts in the Great Lakes (1995–2012), an in-depth review of the resulting imagery and lidar data products, and new information product developments and applications to support environmental and coastal engineering throughout the Great Lakes region. 相似文献
965.
Takele Zeleke Ahmed Moustafa Moussa Mohamed S. El‐Manadely 《Lakes & Reservoirs: Research and Management》2013,18(4):366-371
Angereb Dam, located in Ethiopia, was constructed in early 1994 as a water supply for the town of Gondar up to the year 2020. The reservoir could not achieve this objective, however, because of significant sedimentation problems. Accordingly, one objective of this study was to simulate the historical reservoir sedimentation pattern, as well as predict the near future (until 2015) sedimentation pattern of Angereb Reservoir. The Sedimentation and River Hydraulics one‐dimensional model (SRH‐1D), version 2.6, was used for this purpose. Another objective was to propose possible mitigation measures to reduce the quantity and rate of sedimentation in the reservoir. There was generally good agreement between measurements and model simulations, with the observed trends being well simulated. The exception was that the model tended to overpredict the sediment deposition volumes in the upstream reaches of the reservoir. The two mitigation alternatives for addressing the sedimentation problem, namely managing sediments in the watershed and flushing sediment through the dam bottom outlet, appear to be technically feasibility, with a predicted reduction of the volume of deposited sediment between 63 and 80% be achievable. 相似文献
966.
A quasi-maximum likelihood procedure for estimating the parameters of multi-dimensional diffusions is developed in which the transitional density is a multivariate Gaussian density with first and second moments approximating the true moments of the unknown density. For affine drift and diffusion functions, the moments are exactly those of the true transitional density and for nonlinear drift and diffusion functions the approximation is extremely good and is as effective as alternative methods based on likelihood approximations. The estimation procedure generalises to models with latent factors. A conditioning procedure is developed that allows parameter estimation in the absence of proxies. 相似文献
967.
Metin Balikcioglu Paul L. Fackler Robert S. Pindyck 《Resource and Energy Economics》2011,33(3):761-768
Two papers of Pindyck, 2000, Pindyck, 2002 that modeled the control of stock pollutants as optimal stopping problems contained closed form solutions that are incorrect. This paper discusses a subtle error in the derivation and demonstrates how solutions to these and related problems can be obtained numerically. The numerical solutions are contrasted with the ones contained in Pindyck's original papers. 相似文献
968.
N. I. Komkov V. V. Sutyagin I. E. Frolov G. G. Balayan G. K. Kulakin M. V. Krotova I. I. Figurkova N. N. Bondareva N. N. Volodina A. A. Lazarev V. S. Romantsov T. V. Maistruk L. V. Shinkaruk V. M. Geets T. V. Golikova S. I. Kireev V. I. Muntiyan L. A. Musina L. I. Fedulova V. K. Khaustov N. M. Shelud’ko E. V. Shubravskaya N. N. Yakubovskii 《Studies on Russian Economic Development》2011,22(4):365-374
The paper presents the research results of an investigation into the state of scientific, technological, trade and economic interactions between Russia and Ukraine in terms of their potential, prospects, and problems impeding their cooperation. It is shown that there is a considerable scientific and technological potential both in Russia and Ukraine. Opportunities and conditions for the modernization of both countries’ economies are shown to depend on the coordinated use of their potentials. 相似文献
969.
This article discusses the limitations of present methods of analyzing the coverage of advertising schedules and presents a technique for obtaining additional information from traditional measures of schedule coverage. This technique models entire patters of audience exposure to commercials by means of a compound Bernoulli distribution that can be estimated from reach and frequency data. Knowledge of the complete pattern of audience exposure to advertising schedules assists the media analyst in selecting optimally effective advertising schedules and consequently enhances the probability of conducting a successful advertising campaign. 相似文献
970.
S. Kirk Elwood 《The Journal of economic education》2013,44(4):381-386
The author explores the problems of portraying oil-price shocks using the aggregate demand/aggregate supply model. Although oil-price shocks are the most commonly cited examples of aggregate supply shocks, they violate the model's assumption of constant relative prices (as acknowledged by the label, “oil-price shocks”). The resulting problems are effectively masked in textbook presentations by implicitly assuming that the supply shocks occur in a closed economy. However, the typical discussion is glaringly inaccurate when discussing the effects of oil-price shocks on oil-rich countries. Thus, the cogency of the standard model's representation of oil-price shocks on open economies is compromised. A simple modification of the model that differentiates between production and absorption goods enables it to better reflect the effects of oil-price shocks on open economies. 相似文献