Efficient estimation of semiparametric conditional moment models with possibly nonsmooth residuals

This paper considers semiparametric efficient estimation of conditional moment models with possibly nonsmooth residuals in unknown parametric components (θ) and unknown functions (h) of endogenous variables. We show that: (1) the penalized sieve minimum distance (PSMD) estimator can simultaneously achieve root-n asymptotic normality of and nonparametric optimal convergence rate of , allowing for noncompact function parameter spaces; (2) a simple weighted bootstrap procedure consistently estimates the limiting distribution of the PSMD ; (3) the semiparametric efficiency bound formula of [Ai, C., Chen, X., 2003. Efficient estimation of models with conditional moment restrictions containing unknown functions. Econometrica, 71, 1795–1843] remains valid for conditional models with nonsmooth residuals, and the optimally weighted PSMD estimator achieves the bound; (4) the centered, profiled optimally weighted PSMD criterion is asymptotically chi-square distributed. We illustrate our theories using a partially linear quantile instrumental variables (IV) regression, a Monte Carlo study, and an empirical estimation of the shape-invariant quantile IV Engel curves.     

TACKLING THE ENDOGENEITY OF FERTILITY IN THE STUDY OF WOMEN'S EMPLOYMENT IN DEVELOPING COUNTRIES: ALTERNATIVE ESTIMATION STRATEGIES USING DATA FROM URBAN BRAZIL

Abstract

Opinions differ about whether family structure, especially fertility, should be considered endogenous in models of behavior in developing countries. Faced with a dearth of good instruments, mainstream researchers often urge working in reduced form and, therefore, losing variables of policy interest or limiting the type of questions they ask to those where good instruments are available. Rather than treating endogeneity as a yes or no characteristic, we suggest instead that researchers consider the likely magnitude of endogeneity bias before moving to reduced form. Facing a situation where endogeneity bias is often presented as a concern but where we expect little endogeneity bias, we tackle endogeneity using multiple econometric techniques not available to the average researcher. We find support for our hypothesis that little bias arises due to the assumption of exogeneity of recent fertility in a model of women's employment.     

The impact of board size on firm performance: evidence from the UK

We examine the impact of board size on firm performance for a large sample of 2746 UK listed firms over 1981–2002. The UK provides an interesting institutional setting, because UK boards play a weak monitoring role and therefore any negative effect of large board size is likely to reflect the malfunction of the board's advisory rather than monitoring role. We find that board size has a strong negative impact on profitability, Tobin's Q and share returns. This result is robust across econometric models that control for different types of endogeneity. We find no evidence that firm characteristics that determine board size in the UK lead to a more positive board size–firm performance relation. In contrast, we find that the negative relation is strongest for large firms, which tend to have larger boards. Overall, our evidence supports the argument that problems of poor communication and decision-making undermine the effectiveness of large boards.     

Engineering robust instruments for GMM estimation of panel data regression models with errors in variables: a note

Econometricians have long recognized the need to account in some way for measurement errors, specification errors and endogeneity to ensure that the ordinary least squares estimator is consistent. This article introduces a new generalized method of moments estimator that relies on robust instruments to estimate panel data regression models containing errors in variables. We show how this GMM approach can be generalized for the panel data framework using higher moments and cumulants as instruments. The new instruments, engineered for greater robustness, are proposed to tackle the pervasive problem of weak instruments.     

高新技术产业园区创新活动内生性与效率 ——基于非平衡面板内生随机前沿模型的分析

基于非平衡面板内生随机前沿模型,通过2009-2019年54个高新技术产业园区的非平衡面板数据,分析了高新技术产业园区创新活动的内生性与效率的关系.研究发现:科技经费和从业人员存在内生性,市场结构、科技经费和从业人员对创新效率有显著的正面影响;面板内生随机前沿模型可以显著地区别于外生随机前沿模型的创新效率估计.     

Divestitures,privatization and corporate performance in emerging markets

We use new firm‐level data to examine the effects of firm divestitures and privatization on corporate performance in a rapidly emerging market economy. Unlike the existing literature, we control for accompanying ownership changes and the fact that divestitures and ownership are potentially endogenous variables. We find that divestitures increase the firm's profitability but do not alter its scale of operations, while the effect of privatization depends on the resulting ownership structure – sometimes improving performance and sometimes bringing about decline. The effects of privatization are thus more nuanced than suggested in earlier studies. Methodologically, our study provides evidence that it is important to control for changes in ownership when analyzing divestitures and to control for endogeneity, selection and data attrition when analyzing the effects of divestitures and privatization.     

Gender Diversity in the Boardroom and Firm Financial Performance

The monitoring role performed by the board of directors is an important corporate governance control mechanism, especially in countries where external mechanisms are less well developed. The gender composition of the board can affect the quality of this monitoring role and thus the financial performance of the firm. This is part of the “business case” for female participation on boards, though arguments may also be framed in terms of ethical considerations. While the issue of board gender diversity has attracted growing research interest in recent years, most empirical results are based on U.S. data. This article adds to a growing number of non-U.S. studies by investigating the link between the gender diversity of the board and firm financial performance in Spain, a country which historically has had minimal female participation in the workforce, but which has now introduced legislation to improve equality of opportunities. We investigate the topic using panel data analysis and find that gender diversity – as measured by the percentage of women on the board and by the Blau and Shannon indices – has a positive effect on firm value and that the opposite causal relationship is not significant. Our study suggests that investors in Spain do not penalise firms which increase their female board membership and that greater gender diversity may generate economic gains.     

Local tax interaction and endogenous spatial weights based on quality of life

This paper studied the role of municipal quality of life as a driver of strategic tax interactions among local governments. A number of studies point out the existence of strategic interactions using spatial econometric models in which the spatial weights are mostly based on non-economic criteria or basic economic variables such as per capita gross domestic product (GDP). We propose the more sophisticated well-being indicator of municipal quality of life as the driver for these interactions. To deal with the potential endogeneity, we rely on instrumental variable estimators. The empirical analysis focuses on the main local tax in Spain (property) and on municipalities with more than 50,000 inhabitants, and it confirms the relevance of differentials in quality of life for the understanding of tax choices.     

Price Endogeneity and Food Demand in Urban China

Price endogeneity has been ignored in previous analyses of food demand in urban China. We exploit data provided by the China National Bureau of Statistics on agricultural commodity supply shifters and use reduced‐form price equations to account for price endogeneity. Applying our unique econometric approach to the analysis of provincial‐level food demand in China, we find strong statistical evidence of price endogeneity. Models that ignore price endogeneity result in substantially biased elasticities and misleading estimates of future food demand in China.     

中国上市公司债务期限结构分析

对我国上市公司债务期限结构影响因素进行检验的结果表明,我国上市公司债务期限结构的影响因素较为稳定,内生性对其不构成显著影响.我国上市公司的债务期限与企业规模正相关,与企业财务实力、资本结构负相关,与其他因素没有显著关系.对债务期限和成长性关系的检验结果表明,我国企业应对成长机会变化的工具是财务杠杆而不是债务期限.代理成本理论不能解释我国上市公司债务期限结构的选择行为.