Top dominance and the possibility of strategy-proof stable solutions to matching problems

Summary This paper explores the possibility of designing strategy-proof mechanisms yielding satisfactory solutions to the marriage and to the college admissions problem. Our first result is negative. We prove that no strategy-proof mechanism can always choose marriages that are individually rational and Pareto efficient. This strengthens a result by Roth (1982) showing that strategy-proof mechanisms cannot always select stable marriages. The result also applies, a fortiori, to college admissions. Since finding difficulties with strategy-proofness is quite an expected result, we then address a second question which is classical within the incentives literature. Are there restrictions on the preferences of agents under which strategy-proof and stable mechanisms do exist? We identify a nontrivial restriction on the domain of preferences, to be called top dominance, under which there exist strategy-proof and stable mechanisms for both types of matching problems. The mechanisms turn out to be exactly those that derive from the most classical algorithms in the literature; namely, the women's optimal, the men's optimal and the student's optimal. Finally, top dominance is shown to be essentially necessary, as well as sufficient, for the existence of strategy-proof stable matching mechanisms.This work is partially supported by grant PB 89-0294, from the Directión General de Investigatión Ciencia y Tecnología of the Spanish Ministerio de Educación y Ciencia. Salvador Barberà is also grateful to the Instituto de Estudios Fiscales. This research was initiated while both authors were visting GREMAQ, Université des Sciencies Sociales, Toulouse, whose hospitality is gratefully acknowledged. The paper extends results that were circulated as GREMAQ W.P. 91.22.232. We are grateful to Matthew Jackson and Marilda Sotomayor for their comments.     

论用文化增加旅游商品的附加值

旅游的本质属性是文化属性。文化是旅游消费和旅游经营追求的核心因素。文章以上述观点为基础，探讨了旅游商品开发设计中文化因素的作用，提出文化可以创造旅游商品，文化可以增加旅游商品的附加值。     

Category management and consumer choice

This paper shows the results of an exploratory analysis of the structure of a complex product category: Wine. In complex categories, a usual strategy of consumers is the partitioning of alternatives into homogeneous subsets and the sequential eliminations of subsets until a product/brand is chosen from among few homogeneous alternatives in the last subset. To identify if there is such a kind of strategy and the product attributes involved is of great interest for the retailer. After a discussion of the different modelling alternatives of the choice process, the authors provide an application of the additive trees (ADDTREE) model to explore the hierarchical structure. The ADDTREE results provide a first overview of the competitive market structure of the wine category: competition becomes more intense as the wine category is partitioned by, first, the type of wine criteria and, second, the designation of origin (DO) criteria.     

Market challenges facing academic research in commercializing nano-enabled implantable devices for in-vivo biomedical analysis

This article reports on the research and development of a cutting-edge biomedical device for continuous in-vivo glucose monitoring. This entirely public-funded process of technological innovation has been conducted at the University of Barcelona within a context of converging technologies involving the fields of medicine, physics, chemistry, biology, telecommunications, electronics and energy. The authors examine the value chain and the market challenges faced by in-vivo implantable biomedical devices based on nanotechnologies. In so doing, they trace the process from the point of applied research to the final integration and commercialization of the product, when the social rate of return from academic research can be estimated. Using a case-study approach, the paper also examines the high-tech activities involved in the development of this nano-enabled device and describes the technology and innovation management process within the value chain conducted in a University–Hospital–Industry–Administration–Citizens framework. Here, nanotechnology is seen to represent a new industrial revolution, boosting the biomedical devices market. Nanosensors may well provide the tools required for investigating biological processes at the cellular level in vivo when embedded into medical devices of small dimensions, using biocompatible materials, and requiring reliable and targeted biosensors, high speed data transfer, safely stored data, and even energy autonomy.     

The Power of the Euro–Sterling Rates in Explaining Asset Market Rates: A High‐frequency Analysis

This article makes use of high‐frequency asset market data to explain unexpected changes in interest rates using the methodology proposed by Cochrane and Piazzesi (2002) . This work departs from the existing literature because it uses UK market expectations to capture unexpected movements in the base rate, and explores its effect on a large number of asset market variables. Results indicate that the relation between asset market data and unexpected base rate changes is stronger and more consistent than the relation between asset market data and raw base rate changes. Results appear to be robust to extreme value changes.     

The accomplishment of the Maastricht criteria with respect to initial debt

The reduction of government debt to 60% of the GDP in order to satisfy the requirements of the Maastricht Treaty for participation in the European Monetary Union is one of the primary economic-policy goals for most of the European Union countries. The first aim of the present paper is to characterize the optimal path of the primary surplus that leads to the achievement of this Maastricht target. Using optimal-control theory we are able to determine an upper bound of the public-debt-to-GDP ratio above which no retrenchment policy becomes effective. The second issue taken up is that of the sensitivity analysis with respect to the initial level of the debt-to-GDP ratio, the growth rate of the economy, the interest rate, the inflation rate, and the inverse of the velocity of the monetary base circulation.     

愿消费经济学的园地永远繁花似锦--祝贺《消费经济》创刊20周年

尹世杰教授是我尊敬的老朋友，老学者。他毕生忠诚于马克思主义经济理论特别是消费经济学的教学与研究工作，成绩卓著，为我国社会主义消费经济的建立和发展作出了巨大贡献。兹逢《消费经济》创刊20周年，特函表示诚挚的祝贺，望继续努力，再创辉煌。     

Relationship Lending and Credit Quality

We analyse whether relationship lending reduces borrowers’ probability of default and, if so, whether this beneficial effect also applies to borrowers who are more exposed to the economic downturn. By using unique, matched data of 43,000 firms and their lending institutions between 2008 and 2010, we document that the probability that a firm becomes distressed decreases if the creditor concentration is high and if the duration of bank-firm relationships is long. While these results appear to support the beneficial effect of relationship lending practices, we note that the organisational distance of banks also matters both as a determinant of loan distress and loan downgrading. The results are stronger for smaller firms.