Blocked-Error-R 2: A Conceptually Improved Definition of the Proportion of Explained Variance in Models Containing Loops or Correlated Residuals

Bentler and Raykov (2000, Journal of Applied Psychology 85: 125–131), and Jöreskog (1999a, http://www.ssicentral.com/lisrel/column3.htm, 1999b http://www.ssicentral. com/lisrel/column5.htm) proposed procedures for calculating R ² for dependent variables involved in loops or possessing correlated errors. This article demonstrates that Bentler and Raykov’s procedure can not be routinely interpreted as a “proportion” of explained variance, while Jöreskog’s reduced-form calculation is unnecessarily restrictive. The new blocked-error-R ² (beR ²) uses a minimal hypothetical causal intervention to resolve the variance-partitioning ambiguities created by loops and correlated errors. Hayduk (1996) discussed how stabilising feedback models – models capable of counteracting external perturbations – can result in an acceptable error variance which exceeds the variance of the dependent variable to which that error is attached. For variables included within loops, whether stabilising or not, beR ² provides the same value as Hayduk’s (1996) loop-adjusted-R ². For variables not involved in loops and not displaying correlated residuals, beR ² reports the same value as the traditional regression R ². Thus, beR ² provides a conceptualisation of the proportion of explained variance that spans both recursive and nonrecursive structural equation models. A procedure for calculating beR ² in any SEM program is provided.     

煤炭资源型城市聚集经济与城市化水平研究

运用可变权系数综合评价模型对2002年中国煤炭资源型城市城市化水平进行测度;基于1999～2002年度煤炭城市面板数据,应用随机效应模型估计煤炭城市聚集经济水平;结果表明,我国煤炭城市城市空间经济结构效率和其城市化水平并不具有正相关性,许多城市化水平相对较高的煤炭城市的聚集经济较差,并没有显示出城市化经济的优势.     

债务融资的治理效应:理论分析与实证检验

首先就西方财务学关于债务治理效应的理论进行了综述，然后采用中国上市公司的经验数据，对债务融资比例与企业绩效指标的关系进行了检验，得出了债务治理效应不佳的结论。这一结论似乎与西方财务学对债务治理效应的主流分析不符。通过分析其中的现实原因，就如何改善中国企业的债务治理效应，提出了相应的政策建议。     

公司价值评估中管理者柔性的价值评估研究

现在公司价值评估方法往往没有考虑到对管理柔性价值定价问题。由于管理柔性价值定价是一种类似期权的定价，因此本运用Black—Scholes期权定价模型和买权卖权平价关系，定价管理柔性价值，来完善公司价值评估中的折现现金流量模型。     

产业组织角度的合作R＆D研究述评

合作R＆D是企业整合研发资源的有效组织形式。本文对产业组织角度的合作R＆D研究进行了较为细致的综述。首先列举了对合作R＆D理论具有一定影响的经验研究；然后梳理了产业组织角度的合作R＆D主流理论；之后介绍了较有代表性的非主流理论研究；最后是全文结论和留待进一步研究的论题。     

让精读课活起来——浅谈课堂上调动学生积极性的几个方法

大学外语教学中的精读课,其教学效果直接影响学生们的学习质量。找到适合自己和学生们的教学方法,就一定会调动师生双方的积极性,做到教学相长,寓教于乐。     

“一带一路”倡议下我国重点省市物流绩效评价研究

物流建设是“一带一路”倡议发展的重点。通过物流设施建设、拓展物流业发展的新方向,促进地区融合、加强多边贸易、加速互联互通,是我国现行经济格局下“一带一路”重点建设省市物流发展的新走向。文章从政府行为、社会效益、服务水平三个维度构建了包含地区经济、物流政策、数字物流等14个指标的物流绩效评价指标体系,利用数据包络法对我国“一带一路”重点建设省市的物流绩效进行评价,发现我国物流业发展存在地区差异大、服务水平过低的现象。结合地方政府的政策解读,发现我国地区物流绩效水平呈现出一定的政策相关性,可通过合理的政策引导促进地区物流业的发展。     

Who are better monitors? Comparing styles of supervisory and independent directors

This paper compares the unobservable style effect between independent directors and supervisory directors on firm performance. Utilizing the unique Chinese board system with both independent and supervisory directors and a large panel data of 2,240 public firms from 2003 to 2017, this paper finds that both supervisory and independent style is crucial in determining variations of firm performance. The effects of both independent and supervisory director style are less significant when the “type II” agency problem is more severe in a firm. Moreover, outside independent director style is more effective when information costs are low or when firms need more outside resources, while inside supervisor director style is more effective when there are no major internal changes. Finally, the results also suggest that increasing qualified supervisor representations are beneficial to firms.     

Convenient estimators for the panel probit model: Further results

Bertschek and Lechner (1998) propose several variants of a GMM estimator based on the period specific regression functions for the panel probit model. The analysis is motivated by the complexity of maximum likelihood estimation and the possibly excessive amount of time involved in maximum simulated likelihood estimation. But, for applications of the size considered in their study, full likelihood estimation is actually straightforward, and resort to GMM estimation for convenience is unnecessary. In this note, we reconsider maximum likelihood based estimation of their panel probit model then examine some extensions which can exploit the heterogeneity contained in their panel data set. Empirical results are obtained using the data set employed in the earlier study. Helpful comments and suggestions by Irene Bertschek and Michael Lechner are gratefully acknowledged. This paper has also benefited from comments by two anonymous referees and from seminar participants at the Center for Health Economics at the University of York. Any remaining errors are the responsibility of the author.     

Winner-take-all price competition

Summary. We analyze an oligopoly model of homogeneous product price competition that allows for discontinuities in demand and/or costs. Conditions under which only zero profit equilibrium outcomes obtain in such settings are provided. We then illustrate through a series of examples that the conditions provided are “tight” in the sense that their relaxation leads to positive profit outcomes. Received: April 7, 2000; revised version: September 14, 2000