On estimating long-run effects in models with lagged dependent variables

A common procedure in economics is to estimate long-run effects from models with lagged dependent variables. For example, macro panel studies frequently are concerned with estimating the long-run impacts of fiscal policy, international aid, or foreign investment.Our analysis points out the hazards of this practice. We use Monte Carlo experiments to demonstrate that estimating long-run impacts from dynamic models produces unreliable results.Biases can be substantial, sample ranges very wide, and hypothesis tests can be rendered useless in realistic data environments. There are three reasons for this poor performance. First, OLS estimates of the coefficient of a lagged dependent variable are downwardly biased in finite samples. Second, small biases in the estimate of the lagged, dependent variable coefficient are magnified in the calculation of long-run effects. And third, and perhaps most importantly, the statistical distribution associated with estimates of the LRP is complicated, heavy-tailed, and difficult to use for hypothesis testing. While many of the underlying problems have been long-known in the literature, the continued widespread use of the associated empirical procedures suggests that researchers are unaware of the extent and severity of the estimation problems. This study aims to illustrate their practical importance for applied research.     

上市公司治理结构效率评估

建立有效的公司治理结构无论对于所有者还是对于投资者而言都是有利的。基于诸如委托代理人理论、不对称信息理论等前沿理论成果,兼顾考虑到正在发展中的中国资本市场环境,本文运用数据包络分析(DEA)分析和研究了中国上市公司治理结构的有效性和效率。     

中国新型工业化道路探索研究——来自印度新型工业化案例的启示

经过大规模传统工业化,中国过早出现了需求不足、资源枯竭、环境污染、就业压力大等问题,这说明传统工业化和现代化的经济发展政策,不适用于当代环境和条件。中国要解决上述问题,必须改变经济增长方式,不能走西方国家发展的老路。而印度新型工业化案例告诉我们,发展中大国完全可以实施赶超型发展战略,即将发展的重点放到国际水平的高新技术产业上,利用高新技术产业的高增殖能力,积累资金和技术,引导和改造传统产业,并积极发展现代服务业,即走以高新技术产业为先导的新型工业化道路。     

社群营销模式创新研究——以“黎贝卡的异想世界”为例

在客户关系社会化的基础上,企业营销模式不断创新,其中以社群成员为主要营销对象的社群营销模式取得了显著效果。本文以"黎贝卡的异想世界"为研究对象,分析了社群营销模式的运用及成果,为中小企业营销模式创新提供一些思路。     

Economics of compatibility standards and competition in telecommunication networks

The pro- and anti-competitive implications of technical compatibility standards are introduced in general terms and then applied to current issues in telecommunications policy. The demand and supply for standards under regulated monopoly and the transition to deregulation and competitive entry create a tradeoff between the traditional goal of achieving positive externalities from interconnection and the alternative goal of providing enhanced service offerings that may involve sacrificing universal connectivity. We argue that this tradeoff has affected the utilization of data communication networks in the U.S. and Europe. In addition, we identify problems of competing interests that complicate the European approach to standards “harmonization” in the case of telecommunications. We conclude by noting that the nature of standards and standard-setting process can have marked effects on the incentives to conduct private research and development.     

广告收入上限的规制涵义--基于电视产业的分析

文章在电视产业规制实践的基础上,把节目编排作为衡量电视传播企业的主要产出,在理论上证明了当观众的总需求固定时,三类电视频道都存在基于DEA的广告收入上限,其规制涵义在于,当把广告收入看作规制者给予电视传播企业的一种转移支付的形式时,基于DEA的广告收入上限给出了促进三种经营方式竞争的规制框架,因此,国家对广告收入上限的规制有着合理的理论基础。     

Dynamic efficiency evaluation of Italian judicial system using DEA based Malmquist productivity indexes

The aim of this study is the empirical analysis of the Italian judicial system, measuring its efficiency and productivity. For this purpose, in details, the Data Envelopment Analysis (DEA) and Malmquist indexes were used, since they are recognized by the current literature as successful techniques to evaluate the performance of decision making units, namely the courts of law in our field of application.The statistical data on the administration of justice in Italy, as reported in Dossier n. 11 May 2013, Senate Research Services, Research Office on Institutional Issues, Justice and Culture, XVII legislature, shows that the efficiency crisis of justice in Italy began in the 1970s of the last century, aggravating during the ‘80s, and reaching its most critical moment during the 1990s. Several studies emphasize the relevance of the effects of inefficiency upon the judicial system on the credit and financial markets.The present analysis, using data that covers a wide time span and is disaggregated at district level, has set the goal of measuring the efficiency of the individual Italian judicial offices while assessing the progress of productivity in its components, by the means of technological progress and scale efficiency. The efficiency analysis that was carried out transcends the aspect of judicial taxation, considering how the passage of time has impacted on judicial efficiency.Considering the judges and judicial administration employed, in the new, pending and finished cases during the years ranging from 2011 to 2016, the results highlighted a distinct heterogeneity among courts, depending on their geographical location. The five-year period that was considered, included the years in which the judicial geographical distribution reform entered into force, so to better comprehend how this complex reform influenced the recovery of efficiency of the judicial offices. Furthermore, by breaking down the index into change in efficiency and change in technology, this work offers a further glimpse into judiciary organization. The application of combined DEA method and Malmquist indexes for evaluating court efficiency in a large time frame showed very interesting and useful results, relevant for judicial administration.     

Internet of Things and Big Data as enablers for business digitalization strategies

Digitization blurs the lines between technology and management, facilitating new business models built upon the concepts, methods and tools of the digital environment. The purpose of this study is to investigate the role of the Internet of Things (IoT) and Big Data in terms of how businesses manage their digital transformation. The paper argues that the outbreak of IoT and Big Data has resulted in a mass of disorganized knowledge. In order to make sense of the noise, a literature review was carried out to examine the studies, published in the last decade (2008–2019), that analyzed both the Internet of Things and Big Data. The results show that IoT and Big Data are predominantly reengineering factors for business processes, products and services; however, a lack of widespread knowledge and adoption has led research to evolve into multiple, yet inconsistent paths. The study offers interesting implications for managers and marketers, highlighting how the digital transformation enabled by IoT and Big Data can positively impact many facets of business. By treating IoT and Big Data as faces of the same coin, this study also sheds light on current challenges and opportunities, with the hope of informing future research and practice.     

数据仓库相关问题的探讨

综述了数据仓库的概念、特点、结构及其关键技术，对创建数据仓库系统过程中存在的有关问题进行了探讨，并展望了其发展趋势。     

Why you should use high frequency data to test the impact of exchange rate on trade

This study suggests that testing the impact of exchange rate on trade should be done using high-frequency data. Using different data frequencies for identical periods and specifications between the US and Canada, we show that low-frequency data might suppress and distort the evidence of the impact of exchange rate on trade in the short run and the long run.