Testable implications of general equilibrium models: An integer programming approach

Focusing on the testable revealed preference restrictions on the equilibrium manifold, we show that the rationalizability problem is NP-complete. Subsequently, we present a mixed integer programming (MIP) approach to characterize the testable implications of general equilibrium models. Attractively, this MIP approach naturally applies to settings with any number of observations and any number of agents. This is in contrast with existing approaches in the literature. We also demonstrate the versatility of our MIP approach in terms of dealing with alternative types of assignable information. Finally, we illustrate our methodology on a data set drawn from the US economy. In this application, an important focus is on the discriminatory power of the rationalizability tests under study.     

Dynamics of Customer Response to Promotional and Relational Direct Mailings from an Apparel Retailer: The Moderating Role of Relationship Strength

Although direct mails have traditionally been used to sell a product or service, they can also be effective in enhancing retailer-customer relationships. This study examines how customers respond to ‘promotional’ (‘call to action’) and ‘relational’ (‘retailer-image enhancement’) direct mailings. The study develops a model that includes: (i) the dynamic effects of both types of direct mailings over time; and (ii) the moderating role of strength of the relationship that a customer enjoys with the retailer. Past purchase behavior is also considered. The model is then used in a study of customers of a Belgian apparel retailer. The results show that relational mailings positively affect customer response, irrespective of when they are sent. In contrast, the effects of promotional mailings are less clear-cut: although they work well in the short term, their effects can vary in the longer term. In addition, the study finds that a direct-mailing strategy should be planned in accordance with the strength of the relationship between the retailer and the target customers. The results of the study provide valuable insights for retailers in optimizing the effectiveness of their direct-mail initiatives.     

Estimating intergenerational schooling mobility on censored samples: consequences and remedies

In this paper we estimate the impact of parental schooling on child schooling, focus on the problem that children who are still in school constitute censored observations, and evaluate three solutions to it: replacement of observed with expected years of schooling, maximum likelihood approach, and elimination of all school‐aged children. Using intergenerational data from the Wisconsin Longitudinal Study we test how the three correction methods deal with censored observations. The one that treats parental expectations as if they were realizations seems to fix the censoring problem quite well. Copyright © 2009 John Wiley & Sons, Ltd.     

Group lending and individual lending with strategic default

Papers that compare group lending and individual lending in the presence of strategic default suggest that unless group members can impose costly social sanctions on one another, or unless the bank uses cross-reporting mechanisms group lending may do worse than individual lending. In this paper, we show that if, (1) the amount that a successful borrower owes for his defaulting partner is optimally determined, and (2) the penalty is allowed to vary across group members, then even in the absence of any social sanctions or cross-reporting, (1) expected borrower welfare is strictly higher with group lending when both group lending and individual lending are feasible and (2) group lending is feasible for a greater range of opportunity cost of capital. These results are robust to collusion between borrowers.     

Theories of the firm, competitive advantage and government policy

To improve the effectiveness of government policy, it is necessay to develop a good picture of what a firms in a knowledge-intensive economy is and does. In this paper, we have drawn on the recent surge of books and articles on the resource- and knowledge-based theories of the firm and their implications for competitive advantage. We would like to contribute to that discussion summarizing that debate and exploring the implications for government policy. In new theories of the firm, emphasis is placed on the crucial importance of knowledge, a production factor which is not easily imitated. Exampb of government policy which are based on these new inskhts are the recognition of the importance of demanding clients, the emphasis on the unique potential of the local business environment and the stimulation of transfer of knowledge between firms and networks instead of subsidizing project for knowledge development in isolated firms. A more realistic view of business behaviour will improve the effectiveness of policy, thereby generally improving the competitive position of firms.     

城市旅游可持续竞争力评价——以河北省11市为例

目前城市旅游是许多城市进行竞争、争夺市场的有效途径,具有较强的城市旅游可持续竞争力才能使城市在市场中保证持久、稳定的竞争。文章构建了城市旅游可持续竞争力评价指标体系,运用主成分分析法对评价指标进行定量分析计算,对河北省11个地级市的城市旅游可持续竞争力进行了综合评价,并对结果进行比较分析,给出了城市旅游可持续竞争力的差异化原因及提升建议。     

广西北部湾信息产业发展优势与发展重点研究

信息产业是国民经济的先导产业,信息产业的发展能提高国民经济的发展水平。广西北部湾经济区的信息产业发展水平低下。本文主要分析了广西北部湾各城市信息产业发展的现状及其优势,进而提出了北部湾信息产业需要发展的重点方向。     

Analytical analysis of a generic assembly system

The assembly of components is a key element in manufacturing facilities. Nevertheless, literature analyzing the dynamic behavior remains scarce. The paper narrows this gap by studying a generic first-come first-serve assembly system, consisting of two generally distributed component input streams. The field of probability theory serves as a means to derive good approximations for the waiting time of the components to form a kit and the inter-arrival time of the kits at the assembly station. Apart from providing insight in generally accepted managerial principles, this analysis also constitutes a required step in obtaining the performance of an open queuing network including assemblies.     

EU/US Open Skies – Competition and change in the world aviation market: The implications for the Irish aviation market

The EU/US Open Skies agreement became operational on March 29th, 2008. The 23% increase in flights between Ireland and the US in 2008 under the agreement is the highest expected increase under the agreement and is almost three times greater than the expected overall increase in air travel between the EU and the US. Open Skies increases the number of routes between Ireland and the US by 3 to 10 and allows airlines to fly directly to and from Dublin without a compulsory stop at Shannon. There are very strong economic, investment, visitor, political and ethnic ties between Ireland and the US and air travel between the countries per head of population in Ireland is 5.6 times greater than the EU average. The benefits from Open Skies include lower fares, new routes and direct services reducing the need to backtrack over European hubs, in addition to the abolition of the requirement to stopover at Shannon.     

Critical issues facing R&D managers in China

R&D managers in China experienced significant changes in the past decade, in particular because of Government policies of economic reform and opening to the outside world. These developments have brought about a number of rather specific R&D management issues and problems. The paper addresses the main problems faced by R&D managers in China. First, the current situation of R&D management in China is discussed, as well as the future developments. The paper then presents a case study of the CISRI (Central Iron & Steel Research Institute), a large comprehensive R&D organisation in Beijing. The analysis leads to the critical issues in CISRI's R&D management. After that, a further investigation is described into the trends of Chinese R&D management. The outcomes described focus on the future of R&D management in China as well as on the integration of Western R&D management theory in China. The paper concludes with the major issues and recommendations for the further development of R&D management in China.