Robust portfolio optimization

We address the problem of estimating risk-minimizing portfolios from a sample of historical returns, when the underlying distribution that generates returns exhibits departures from the standard Gaussian assumption. Specifically, we examine how the underlying estimation problem is influenced by marginal heavy tails, as modeled by the univariate Student-t distribution, and multivariate tail-dependence, as modeled by the copula of a multivariate Student-t distribution. We show that when such departures from normality are present, robust alternatives to the classical variance portfolio estimator have lower risk.     

Spousal Effect and Timing of Retirement

The retirement decisions of individuals are strongly influenced by spousal retirement, financial incentives and institutional constraints such as access to early retirement benefits. In the European Union (EU), farm retirement is encouraged by early retirement provisions for farmers. As exit from farming determines the characteristics of structural change in agriculture, it is important to find out how spousal retirement and economic incentives affect the timing and type of retirement decisions among elderly farmers. This paper analyses the timing of early retirement decisions of farming couples using duration analysis and different exit channels. The empirical analysis is based on Finnish farm‐level panel data for the period 1993–1998. The results suggest that an expected pension particularly advances farm transfers. Farming couples are found to co‐ordinate their early retirement decisions. However, farmers are not found to co‐ordinate their early retirement according to spousal retirement under other pension schemes.     

Re-employment probabilities over the business cycle

Using a Cox proportional hazard model that allows for a flexible time dependence in order to incorporate business cycle effects, we analyze the determinants of re-employment probabilities of young workers in the USA from 1978–1989. We find considerable changes in the chances of young workers finding jobs over the business cycle despite the fact that personal characteristics of those starting jobless spells do not vary much over time. Therefore, government programs that target specific demographic groups may change individuals’ positions within the queue of job seekers, but may only have a more limited impact on average re-employment probabilities. Living in an area with high local unemployment reduces re-employment chances as does being in a long spell of non-employment. However, the damage associated with being in a long spell seems to be reduced somewhat if a worker is unemployed in an area with high overall unemployment.

Towards an understanding of attraction in buyer–supplier relationships

This paper explores how firms are attracted to one another within buyer–supplier dyads. It draws attention to ways of managing in a relational mode as an alternative to managing in a controlling mode. This study argues that in order to improve value creation and value transfer in buyer–supplier relationships it is not enough to optimize and coordinate management and control systems. Following Dwyer et al. [Dwyer, R., Schurr, P.H. and Oh, S. (1987). Developing buyer–seller relationships. Journal of Marketing, 51: 11–27.], it argues that mutual attraction is important in developing relationships. It is also argued that this can be achieved through a range of perceptual approaches and actions, which enhance performance between the parties involved. A conceptual model of attraction is developed with theoretical underpinnings in social exchange theory. It proposes three behavioral constraints: expected value, trust, and dependence. These components of attraction interact to draw dyadic parties closer together or push them apart. Finally, implications for research and practice are discussed.     

对我国外贸"贫困化增长"的再分析

本文根据"贫困化增长"的前提条件,对我国外贸是否存在贫困化增长进行了探索,得出了我国并不存在贫困化增长的现象,最后根据我国现阶段的具体情况,提出了一些防范出现贫困化增长的措施.     

民营企业治理转型困境与超越——基于路径依赖理论的分析视角

随着民营企业由初创期走向“二次创业”阶段,公司治理模式由封闭、集权的家族主导型向开放、制衡型的现代公司治理转变,就成为企业发展壮大的必然要求。然而,这种有利于效率改进的制度变迁却没有普遍发生,企业陷入公司治理模式的转型困境。本文运用路径依赖理论,从初始产权结构、传统文化和企业家行为倾向3个角度分析和揭示了民营企业治理转型困境的路径依赖效应,阐述了要超越和克服路径依赖,必须将注意力集中于发挥国家和企业家等制度变迁主体的积极作用,从而使公司治理模式脱离无效率的“锁定”状态,步入有效率的演进路径。     

新疆对外开放度的测算与比较研究

通过构建外贸依存度、外资依存度、对外开放度等指标体系,对1991-2010年新疆对外开放度进行了测度与分析。并通过与陕西、甘肃、宁夏西部3省及全国平均开放度水平的比较,得出了以下结论:新疆对外开放度的变化趋势与全国大体一致,但外贸依存度和对外开放度等方面远低于全国水平,只有外资依存度略高于全国平均水平;与西部3省相比来看,新疆的对外开放度在2001年之前最低,宁夏和陕西省居高,但2001年之后,新疆省对外开放度迅速增加,到2008年均高于其他3省。同时分析了新疆外开放度相对较低的主要原因,提出了相应的对策和建议。     

人性论下中国式管理的路径锁定与对策

中西方基于性善与性恶基础上的管理制度的设计都形成了各自的路径,并且形成了各自不同的交易成本,中国式管理从短期看成本可能比较低,从长期来看对于个人而言则是高成本。而西方的管理从短期来看成本较高,而从长期来看由于依靠制度而实现低成本运作,并依据力学模型提出打破路径依赖的方法。