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71.
Extant customer-base models like the beta geometric/negative binomial distribution (BG/NBD) predict future purchasing based on customers' observed purchase history. We extend the BG/NBD by adding an important non-transactional element that also drives future purchases: complaint history. Our model retains several desirable properties of the BG/NBD: it can be implemented in readily available software, and estimation requires only customer-specific statistics, rather than detailed transaction-sequence data. The likelihood function is closed-form, and managerially relevant metrics are obtained by drawing from beta and gamma densities and transforming these draws to a sample average. Based on more than two years of individual-level data from a major U.S. internet and catalog retailer, our model with complaints outperforms both the original BG/NBD and a modified version. Even though complaints are rare and non-transactional events, they lead to different substantive insights about customer purchasing and drop-out: customers purchase faster but also drop out much faster. Furthermore, there is more heterogeneity in drop-out rates following a purchase than a complaint. 相似文献
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Naumann RB Dellinger AM Haileyesus T Ryan GW 《International journal of injury control and safety promotion》2011,18(1):65-73
As the US population ages, more older adults will face transportation and mobility challenges. This study examines the characteristics and contributing circumstances of nonfatal older adult pedestrian injuries. Data were obtained from the National Electronic Injury Surveillance System-All Injury Programme (NEISS-AIP) for the years 2001 through 2006. Cases included persons aged 65 years and older who were nonfatally injured on a public roadway. The results indicated that on average, an estimated 52,482 older adults were treated in emergency departments each year for nonfatal pedestrian injuries. Falling and being hit by a motor vehicle were the leading mechanisms of injury, resulting in 77.5% and 15.0% of older adult pedestrian injuries, respectively. More than 9000 older pedestrian fall-related injuries each year involved a kerb. It is concluded that the growth in the older adult population could add to the overall burden of these nonfatal pedestrian injuries. Making transportation and mobility improvements, including environmental modifications, is important for preventing these injuries. 相似文献
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CHETAH, which stands for the Chemical Thermodynamic and Energy Release Program, was introduced in 1974. Since then, the CHETAH program has been widely used in the chemical industry for hazard evaluation. Although its chief aim is to predict deflagration/detonation potential from molecular structure, it can also be used to estimate heats of reaction, heat capacities, and entropies. One of the limitations of the original program was its rigid, punched card oriented format for data input and the lack of an overall hazard rating derived from the several hazard criteria. A new release of this program alleviates these shortcomings and includes other improvements. The main features of the new release are: 1) a totally interactive front end, 2) an interpreter subroutine which uses sophisticated pattern recognition techniques to combine the four hazard criteria into an overall hazard rating, 3) recognition of certain atomic groupings which are known to be sensitive, 4) correct handling of the symmetry number, and 5) an updated data bank. One of the most important features of this release is its availability in an IBM PC compatible version, making the program accessible to more users. 相似文献
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T. Randolph Beard George S. Ford Lawrence J. Spiwak Michael L. Stern 《Managerial and Decision Economics》2018,39(6):638-651
Recent decades have seen a fundamental shift in the nature of economic regulation in the United States. Unauthorized by congress, and largely unnoted in legal and academic circles, regulatory agencies such as the Federal Communications Commission have changed the regulatory process by linking otherwise unrelated regulatory issues. Examples include tying merger approval to firm commitments to engage in conceptually unrelated build‐outs and other projects of political importance. This linking of issues has several effects, the most prominent being (a) tying regulatory issues changes the outcomes obtained, plausibly in predictable ways; (b) tying in some circumstances allows regulators to extend their authority to issues for which they have little or no legal authority; and (c) tied regulatory bargaining fails to produce valid legal precedent for firm decision making. We provide an analysis of these conclusions by examining the increasing use of consent decrees, voluntary merger commitments, and merger conditions by the Federal Communications Commission, referencing our discussion with a simple model of joint bargaining applicable to regulatory practice. 相似文献
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Jue Wang George Athanasopoulos Rob J. Hyndman Shouyang Wang 《International Journal of Forecasting》2018,34(4):665-677
The growing internet concern (IC) over the crude oil market and related events influences market trading, thus creating further instability within the oil market itself. We propose a modeling framework for analyzing the effects of IC on the oil market and for predicting the price volatility of crude oil’s futures market. This novel approach decomposes the original time series into intrinsic modes at different time scales using bivariate empirical mode decomposition (BEMD). The relationship between the oil price volatility and IC at an individual frequency is investigated. By utilizing decomposed intrinsic modes as specified characteristics, we also construct extreme learning machine (ELM) models with variant forecasting schemes. The experimental results illustrate that ELM models that incorporate intrinsic modes and IC outperform the baseline ELM and other benchmarks at distinct horizons. Having the power to improve the accuracy of baseline models, internet searching is a practical way of quantifying investor attention, which can help to predict short-run price fluctuations in the oil market. 相似文献
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George S. Day Bela Gold Thomas D. Kuczmarski 《Journal of Product Innovation Management》1994,11(1):69-75
Product innovation management, by definition, requires that we become comfortable dealing with change. As this journal enters its eleventh year of publication, the editor-in-chief asked each member of the editorial board to reflect upon changes and opportunities that they see influencing our profession during the coming decade. In our first installment of these essays, George Day, Bela Gold and Thomas Kuczmarski discuss the value of managing ideas, embracing a longer-term view of development opportunities, and creating a senior executive position charged with developing such opportunities. Each of these short essays is designed to introduce new perspectives. It is not essential that you agree with the recommendations, but we hope that you are stimulated as you reflect on the issues they present. 相似文献
80.
This study uses the Malmquist index with bias correction to analyze the performance of hotel chains from the UAE, Saudi Arabia and Oman. We show that Saudi Arabia hotel chains have the highest productivity growth, followed by the UAE and Omani hotel chains. A further decomposition of productivity indicates that a small number of hotel chains experienced an increase in revenues for lower occupancy rate, while most other hotel chains experienced an increase in occupancy rate for lower revenues. Related market discussions of the results are provided. 相似文献