Do homeowners achieve more household wealth in the long run?

Despite the public’s faith in homeownership as a vehicle for wealth creation, there are surprisingly few empirical studies of the independent impact of homeownership and its duration on household wealth accumulation. This paper provides the first empirical evidence that homeownership, after controlling for other drivers of wealth accumulation, is positively and significantly associated with wealth accumulation over time. Using the Panel Survey of Income Dynamics, it examines the influence of housing tenure choices between 1989 and 2001 on household net wealth levels in 2001 after controlling for initial wealth in 1989, location, income, education, and other family and personal characteristics that might influence the rate of wealth accumulation. Importantly, the models used also control for the tendency of households to accumulate wealth between 1984 and 1989 (five years prior to the studied period). This approach is used to address the possibility that an unobserved variable—the propensity to save or accumulate wealth—may be associated with both the probability and duration of homeownership and the rate of wealth accumulation. All else equal, those who owned homes and owned for longer periods of time had significantly higher household net wealth by 2001. These results are compelling because house price appreciation over the period was near its long-run average while stock gains were above and real rent increases below their long-run averages. Hence, the findings are suggestive of a positive influence of ownership over long periods on net wealth, even during a period when alternative investments produced higher than normal returns and rents grew slowly. This is especially important because the overwhelmingly majority of households do not sell their homes shortly after buying them. In our sample, those who became owners typically owned for 7 years. Furthermore, most households that bought during a period of declining real home values in the early 1990s continued to own their homes for at least eight years and came out well ahead of those who did not own.     

应用二级CES生产函数对中国制造业R＆D投入产出效应的实证研究

进入知识经济时代，科学技术成为重要的生产要素，而科技创新活动中最重要的是R＆D活动。本文试图从生产过程技术关系的角度，实证地研究目前我国企业R＆D活动的投入产出效应。首先我们在生产函数的投入要素向量中引入R＆D投入变量，然后结合相关的研究经验和本文的研究目的，选择二级CES生产函数模型，并对这类模型的参数估计方法进行了探讨。在此基础上，采用2003年上海主要制造业企业的横截面数据，实证研究了企业R＆D投入的产出效应，以及投入要素之间的替代关系，得到了一些具有启发性的结果。     

VE在油田开发中的应用

孤岛采油厂历经30多年的开发,已处于特高含水期产量递减阶段。由于新井产量受到自然资源和投资的限制是有限的,要减缓原油产量的递减,依靠的是大量增产措施的投入,而每项措施的实施需要耗费几万元到几十万元的费用。所以,引起开发后期油田成本上升的主要原因是油田增产措施难度加大,投入相应增加。为此,我们引入VE原理,科学实施增产措施工作量,达到了降低作业成本,提高增油效果的目的。     

基于集成化供应链的ERP、CRM与SCM的整合

在企业信息化建设进程中,ERP、CRM与SCM作为关键技术在不同的领域中发挥着重要作用。本文运用集成化供应链管理模型,对于如何从供应链的角度出发,实现三者的有机整合进行了探讨,提出了以集成化供应链为基础的将三者集成的设想。     

物流中的新设施—自动化立体仓库

当今物流速度日益加快，仓库建设和改造向空间、立体化、自动化快速发展，建设自动化立体仓库是今后的必然趋势。结合多年实践．对物流领域成件货物储存的新设施，自动化立体仓库进行了详细阐述。     

外资进入武汉物流市场的现状及对策

武汉以优越的地理位置,良好的交通设施,雄厚的科技和产业实力吸引了外资,形成了新的竞争环境,文中以运输环境作为对象,分析了外资进入物流市场给内地物流带来的机遇和挑战.     

基于自组织创新网络的集群式供应链体系研究

基于自组织创新网络理论来分析集群式供应链系统的成因及其架构,介绍了“武汉.中国光谷”的集群式供应链系统,并结合该案例总结集群式供应链进行自组织创新的五个过程。     

LOGIT模型在小额农贷信用风险识别中的应用

小额农贷对满足农民生产、生活中的小额资金需求有重要作用。小额农贷有效实施的关键是信用风险的控制。本文根据小额农贷的特点构造一个LOGIT识别模型，并利用苏北某信用联社贷款数据对模型进行实证检验。LOGIT识别模型结果稳定、可靠，是较理想的农户信用风险识别模型。     

基于集对分析法的地区大中型工业企业自主创新能力评价

为了对地区大中型工业企业自主创新能力进行全面、科学的评价,基于集对分析法,提出了地区大中型工业企业自主创新能力评价指标体系及综合评价模型。通过对我国30个省市区大中型工业企业的实证分析,表明该方法科学简便,具有很好的实用价值。     

企业信用风险度量模型的框架设计

企业信用风险一般是指企业在其外部债务到期时无力偿还，从而使企业自身面临着破产清算的困境，并使债权人遭受损失的可能性。目前，我国企业信用缺失严重，如何科学有效地度量信用风险，以更好地防范和控制风险的恶化已成为理论界和实务界研究的主要课题。本正是在分析了国内外信用度量方法的基础上，针对我国的实际情况，设计了一个“以商业化运作的数据平台为支持，以商业银行为主体，各类征信公司和评级机构为辅助的企业信用风险的综合度量模型”的基本框架。