推广成本信息不对称下推广商与酒店间的合作契约设计

为应对日趋激烈的酒店市场竞争、加强对销售渠道的控制,酒店急需与推广商合作以提高自有销售网站的需求水平。文章基于推广成本信息不对称,构建了一个占主导的酒店和一家推广商关于需求推广合作的博弈模型,分析了信息不对称情形下推广商的谎报动机,指出合作契约设计的必要性。并提出一套契约菜单,在保证推广商依据自身实际成本类型进行契约选择的前提下,实现了酒店利润的最大化。最后通过算例分析,验证了所设计的合作契约的有效性,并给出了参数灵敏性分析。     

Group forecasting accuracy in hotels

Yield management helps hotels more profitably manage the capacity of their rooms. Hotels tend to have two types of business: transient and group. Yield management research and systems have been designed for transient business in which the group forecast is taken as a given. In this research, forecast data from approximately 90 hotels of a large North American hotel chain were used to determine the accuracy of group forecasts and to identify factors associated with accurate forecasts. Forecasts showed a positive bias and had a mean absolute percentage error (MAPE) of 40% at two months before arrival; 30% at one month before arrival; and 10–15% on the day of arrival. Larger hotels, hotels with a higher dependence on group business, and hotels that updated their forecasts frequently during the month before arrival had more accurate forecasts.     

考虑预订取消率的酒店退订政策选择演化博弈研究

基于顾客的取消预订行为,在Hotelling模型框架下构建了酒店的博弈模型,分析了两竞争性酒店退订政策选择的问题。研究表明,当顾客对酒店之间水平差异的敏感程度较高时,若两酒店的预订取消率差异较小,则两酒店都将选择宽松的退订政策;若取消率差异较大,则取消率较高的酒店将选择严格的退订政策,而取消率较低的酒店将选择宽松的退订政策。当顾客对酒店之间水平差异的敏感程度较低且两酒店的预订取消率差异较小时,系统存在两个演化稳定策略,酒店只有选择与竞争对手相反的策略才能获得最大收益。本研究能够为酒店的决策制定和收益管理提供一定的支持。     

A non-radial measure of different systems for Taiwanese tourist hotels’ efficiency assessment

The literature assumes that Taiwan’s international tourist hotels have identical frontier technology to evaluate non-radial efficiencies, even if they characterize different operating types. This study develops a non-radial systems model, for which the different operating types are evaluated based on different frontier technologies in order to calculate efficiencies. Compared to the radial systems model, the new model is able to practice two verifications. First, efficient units can be separated into strong and weak efficient sets. The second finds the benchmark among the different types for each input and output. The empirical results show that most efficient units reflect strong efficiency while only one hotel reflects weak efficiency. Inefficient hotels should refer to the chain type in order to improve excess utilizations in employees, rooms, catering space, and revenue deficits. For improving excess operating expenses and occupancy rate deficits, inefficient hotels should refer to the independent type.     

The impact of tourist destination on hotel efficiency: A data envelopment analysis approach

This paper evaluates the impact of location on hotel efficiency using a sample of 400 Spanish hotels, the novel aspect being that location is considered at the tourist destination level. Moreover, for the first time, the location variables are based on the main theoretical models concerning location in the hotel sector, namely geographical positioning models, agglomeration and urbanization economic models and competitive environment models. The methodology consists of a four-stage data envelopment analysis (DEA) model that decomposes super-efficiency in the portion attributable to the tourist destination and the portion attributable to hotel management. Then, managerial efficiency is regressed against hotel characteristics, while tourist destination efficiency is explained by the characteristic of each location. The findings highlight the importance of tourist destinations, providing novel empirical support for the propositions of the main location models. Indeed, the tourist destination is the main cause of differences in the level of efficiency among hotels. The occupancy level, degree of seasonality and market concentration are the variables with the greater impact on efficiency.     

Yield management for privatised air traffic control?

Air Traffic Control (ATC) ensures the safe and expeditious passage of all aircraft in controlled airspace, usually, airspace above 5000–7000?ft or around main airports. Serious airspace congestion has led to demands for more cost-effective ATC and to plans to privatise air traffic services in the UK. These trends offer numerous opportunities to apply Operational Research in the 21st century, especially to improve information management. In a context of ATC privatisation, this paper investigates how applicable yield management (YM) policies are to European ATC. Necessary conditions for the use of YM are examined and difficulties in using YM for ATC are identified. Following this, possible YM solutions are outlined. Finally, the implications of YM for airspace users are addressed.     

A memetic algorithm for the orienteering problem with hotel selection

In this paper, a memetic algorithm is developed to solve the orienteering problem with hotel selection (OPHS). The algorithm consists of two levels: a genetic component mainly focuses on finding a good sequence of intermediate hotels, whereas six local search moves embedded in a variable neighborhood structure deal with the selection and sequencing of vertices between the hotels. A set of 176 new and larger benchmark instances of OPHS are created based on optimal solutions of regular orienteering problems. Our algorithm is applied on these new instances as well as on 224 benchmark instances from the literature. The results are compared with the known optimal solutions and with the only other existing algorithm for this problem. The results clearly show that our memetic algorithm outperforms the existing algorithm in terms of solution quality and computational time. A sensitivity analysis shows the significant impact of the number of possible sequences of hotels on the difficulty of an OPHS instance.     

考虑预定时间限制的酒店客房定价决策

假定顾客是价格敏感的、房价的变化会带来需求的变化以及酒店可在预定期初调整价格策略以便影响市场需求将客房充分预售的条件下,给出了考虑预定时间限制的酒店客房定价决策模型,分析了最优房价、期望收益随预定时限的变化情况.     

基于收益管理理论的门诊预约存量控制研究

门诊预约机制能够帮助医疗服务系统实现合理的资源组织与顺畅的服务流程,目前是医疗系统管理中的热点问题。论文分析了收益管理的适用性条件,提出其在医院门诊预约调度问题中应用的可行性,然后构建了门诊预约存量控制的Littlewood基础模型,并考虑患者爽约的情况,建立了超订策略下的门诊预约存量控制模型,最终用实例验证了所提出方法的实用性和有效性。     

Dynamic cruise ship revenue management

Recently, it has been recognized that revenue management of cruise ships is different from that of airlines or hotels. Among the main differences is the presence of multiple capacity constraints in cruise ships, i.e., the number of cabins in different categories and the number of lifeboat seats, versus a single constraint in airlines and hotels (i.e., number of seats or rooms). We develop a discrete-time dynamic capacity control model for a cruise ship characterized by multiple constraints on cabin and lifeboat capacities. Customers (families) arrive sequentially according to a stochastic process and request one cabin of a certain category and one or more lifeboat seats. The cruise ship revenue manager decides which requests to accept based on the remaining cabin and lifeboat capacities at the time of an arrival as well as the type of the arrival. We show that the opportunity cost of accepting a customer is not always monotone in the reservation levels or time. This non-monotone behavior implies that “conventional” booking limits or critical time periods capacity control policies are not optimal. We provide analysis and insights justifying the non-monotone behavior in our cruise ship context. In the absence of monotonicity, and with the optimal solution requiring heavy storage for “large” (industry-size) problems, we develop several heuristics and thoroughly test their performance, via simulation, against the optimal solution, well-crafted upper bounds, and a first-come first-served lower bound. Our heuristics are based on rolling-up the multi-dimensional state space into one or two dimensions and solving the resulting dynamic program (DP). This is a strength of our approach since our DP-based heuristics are easy to understand, solve and analyze. We find that single-dimensional heuristics based on decoupling the cabins and lifeboat problems perform quite well in most cases.     

Pricing strategies for perishable products: the case of Vienna and the hotel reservation system hrs.com

Consider a retailer who sells perishable products for which there is uncertain demand. Yield management with dynamic pricing is a standard practice that firms use for revenue management. For perishable products, recent analysis has focused on the distribution of flight capacity, referred to as ticket sales. Other non- storable, non-transportable, immaterial hospitality products include hotel capacity. The article discusses the extent to which hotel pricing strategies vary within the internet distribution system hrs.com. This study focuses on the distribution of hotel rooms available for booking on the internet for Vienna and gives an outlook to Euroland capitals. The main research interests are the underlying pricing models and the setting of the end price. Data was taken from hrs.com, which is the most important specialist for hotel room internet distribution in Germany according to recent studies by KMPG and others. The results include the identification of different pricing strategy clusters with regard to hotel category and hotel availability over a 22-day period for Vienna and one city from all Euroland countries (the capitals were studied for all cases except for the Netherlands, for which data was collected for Amsterdam). The study took the arrival days Mondays, Tuesdays, Wednesdays and Thursdays into account, and used data for all these days from the 11th of July, 2005, to the 10th of October, 2005, for Vienna, and the first and the last of these dates as a comparison base for the other Euroland cities.     

A formal analysis of the model management literature

This paper presents an extensive bibliography of the archival material on model management, and an analysis of that material. It argues that the three general approaches to model management can be observed, called here the data-model analogy, knowledge-based and model-representation approaches. For the period 1970 to 1989, 57 journals were exhaustively searched for articles dealing with model management; 152 articles were identified. An informal analysis shows that model creation and execution have been the major model management functions addressed by research, and that mathematical programming and simulation have been the dominant model areas. Applications have addressed the extremes of Operations Research models, namely policy and strategy at one extreme and operations at the other, with many applications in accounting and finance also prevalent. A formal analysis using factor analysis shows that research in model management has moved away from speculation and focus on certain limited aspects of the subject towards the practical implementation of model management systems. Further, a regression model shows that the model-representation approach has tended to yield implemented systems, whereas the data-model analogy approach has not. Directions for future research and development are suggested.     

Model for imperfect age-based preventive maintenance with age reduction

The effect of ageing on the deterioration rate of most repairable systems cannot be ignored. Preventive maintenance (PM) is performed in the hope of restoring fully the performance of these systems. However, in most practical cases, PM activities will be only able to restore part of the performance. Bridging the gap between theory and practice in this area requires realistic modelling of the effect of PM activities on the failure characteristics of maintainable systems. Several sequential PM models have been developed for predetermined PM interval policies but much less effort has been devoted to age-based ones. The purpose of this paper is to develop an age-based model for imperfect PM. The proposed model incorporates adjustment factor in the effective age of the system. The system undergoes PM either at failure or after a predetermined time interval whichever of them occurs first. After a certain number of such PMs, the system is replaced. The problem is to determine both the optimal number of PMs and the optimal PM's schedule that minimize the total long-term expected cost rate. Model analysis relating to the existence and uniqueness of the optimal solutions is provided. Numerical examples are presented to study the sensitivity of the model to different cost function's factors and to illustrate the use of the algorithm.     

Exact and heuristic algorithms for the Travelling Salesman Problem with Multiple Time Windows and Hotel Selection

We introduce and study the Travelling Salesman Problem with Multiple Time Windows and Hotel Selection (TSP-MTWHS), which generalises the well-known Travelling Salesman Problem with Time Windows and the recently introduced Travelling Salesman Problem with Hotel Selection. The TSP-MTWHS consists in determining a route for a salesman (eg, an employee of a services company) who visits various customers at different locations and different time windows. The salesman may require a several-day tour during which he may need to stay in hotels. The goal is to minimise the tour costs consisting of wage, hotel costs, travelling expenses and penalty fees for possibly omitted customers. We present a mixed integer linear programming (MILP) model for this practical problem and a heuristic combining cheapest insert, 2-OPT and randomised restarting. We show on random instances and on real world instances from industry that the MILP model can be solved to optimality in reasonable time with a standard MILP solver for several small instances. We also show that the heuristic gives the same solutions for most of the small instances, and is also fast, efficient and practical for large instances.     

Conceptual modelling for simulation Part I: definition and requirements

Conceptual modelling is probably the most important aspect of a simulation study. It is also the most difficult and least understood. Over 40 years of simulation research and practice have provided only limited information on how to go about designing a simulation conceptual model. This paper, the first of two, discusses the meaning of conceptual modelling and the requirements of a conceptual model. Founded on existing literature, a definition of a conceptual model is provided. Four requirements of a conceptual model are described: validity, credibility, utility and feasibility. The need to develop the simplest model possible is also discussed. Owing to a paucity of advice on how to design a conceptual model, the need for a conceptual modelling framework is proposed. Built on the foundations laid in this paper, a conceptual modelling framework is described in the paper that follows.     

A formal apparatus for modeling trust in computing environments

Recent research in computer systems security has evolved into trust issues, which are now becoming an important topic. The majority of approaches for trust modeling addressed trust by actually focusing on security, and some of them addressed also trust as such. This paper presents a formal apparatus that concentrates on trust as such. It is flexible enough to accommodate the driving factors behind trust and consequently different trust-focused methodologies and technologies. The basic goal of the work presented in this paper is the definition of qualitative trust modeling methodology for trust management in contemporary computing environments that efficiently complements existing quantitative methodologies. Further, an open conceptual model for trust management is presented that accommodates various qualitative and quantitative trust management methodologies. This model has also been implemented in the web services environment, and this is discussed in this paper as well.     

OPTIMAL CHOICE BETWEEN EVEN‐ AND UNEVEN‐AGED FORESTRY

Abstract Existing optimal rotation models include even‐aged management exogenously into the model structure. As an economic model, this Faustmann framework is restrictive, and a more general model should not include any such preconditions. Even‐aged management should follow endogenously as an optimal solution if it proves out to be superior to other systems, such as uneven‐aged management. Without such a general model, the economically optimal choice between even‐aged and uneven‐aged forestry remains somewhat arbitrary. This study specifies such a model and shows how even‐aged management follows endogenously and reveals what factors work in favor of each management alternative. Numerical analysis shows that even‐ and uneven‐aged systems may represent locally optimal solutions and may yield equal economic outcomes. Instead of the usual comparative statics results of the Faustmann model, changes in the rate of discount, timber price, or planting cost may imply that the optimal solution shifts from even‐ to uneven‐aged management.     

Development of a three-echelon SC model to optimize coordination costs

The purpose of this study is to suggest a conceptual framework for aligning the strategic issues and the structural issues of supply chain management, and also to disclose the effect of E-business application on such an alignment. The number of suppliers, number of tiers, the level of SC integration, order penetration point, lead time, and safety stock are defined as supply chain structural issues, and the characteristics of traded products and buyer–supplier relationship are set as key strategic issues for efficient construction of supply chain structure. E-business application is designed as a moderate variable for the alignment between the strategic issues and the structural issues of supply chain management. Such effort suggests a conceptual framework required for developing an advisable set of E-business application strategies for the efficiency improvement of overall supply chain management. The empirical research model proposed in this work may be used to establish an E-supply chain progression paradigm and a new dimensional manufacturing strategy framework in the E-business era.     

Knowledge-based manpower planning

The capacity performance of knowledge-based systems differs essentially from the one of traditional systems. The result is that already today these systems are employed in a number of application areas, and that the intensity of research and development in this field is very high.In this paper the development of a knowledge-based manpower planning system (KBMS) is described. The two main components of this system are a knowledge-based system developed for management planning and a model designed for manpower planning in personnel leasing companies. This model was realized as a KBMPS by applying the knowledge-based system, which was developed for management planning.