Is assortative matching efficient?

Summary. This paper develops some general conditions under which complementarities between individual agents imply that assortative matching is efficient. Our analysis has four main findings. First, when agents are organized into equal-sized groups, just as in Becker (1973), the presence of within-group complementarities is sufficient for stratification to be efficient. Second, if group sizes vary, assortative matching may not be efficient even though complementarities are present, unless particular functional form assumptions are imposed. Third, the connection between assortative matching, complementarities and efficiency reemerges if one considers sequences of replications of the economy in which individual coalitions are uniformly bounded in size. Fourth, the presence of feedbacks from the composition of group memberships has important effects on efficient allocations and breaks any simple link between assortative matching and efficiency. Together, these results suggest that the characterization of the cross-section evolution of an efficiently sorted economy is likely to be highly complex. Received: September 25, 2001; revised version: February 26, 2002 RID="*" ID="*" We thank William Brock for many helpful conversations and Scott Page for detailed comments on an earlier draft of this paper. The National Science Foundation, John D. and Catherine T. MacArthur Foundation and Center for Urban Land Economic Research have generously provided financial support. Correspondence to: S. N. Durlauf     

Does revenue-expense matching play a differential role in analysts’ earnings and revenue forecasts?

This paper investigates whether matching has differential implications for the accuracy of analysts' earnings and revenue forecasts. We construct a novel measure of firm-level matching and document that matching improves analysts' earnings forecasts to a greater extent than their revenue forecasts. We also document matching's differential impact on analysts' earnings and sales forecasts by proposing a new count metric capturing a wedge in the accuracy of earnings and revenue forecasts. In additional tests, we report that the differential impact of matching is less (more) pronounced in a situation where the balance sheet (income statement) orientation likely dominates. We also report that matching's differential role is weaker (stronger) when firms have high intangible intensity (analysts have appropriate resources or expertise). In short window tests, matching's role in analysts' forecast revisions is more pronounced for earnings than sales forecasts. Overall, these results show how analysts benefit from better revenue-expense matching.     

Two-sided platforms in airport privatization

This paper develops an empirical model to examine the relationship between ownership change and two-sided-platform formation in the air transport industry. We investigate whether privatization enhances the dynamic capabilities of airports so that they more closely resemble a two-sided platform. We study the case of the recent privatization of Brazilian airports. We find evidence of a permanent, ceteris paribus increase in demand triggered after the privatization program. The results are consistent with a preemption of assets with a view to expanding operations and so benefiting from the network effects offered by a two-sided platform.     

Analysing and modelling some effects of solutions for matching the airport runway system capacity to demand

The paper deals with analysing and modelling some effects of three solutions for matching the airport runway system (landing) capacity to corresponding demand. These are: i) charging congestion applied to the NY LaGuardia airport (New York, USA); ii) deployment of the innovative operational procedures supported by the new technologies developing in the scope of European SESAR (Single European Sky ATM Research) and U.S. NextGen (Next Generation) program applied to the system of two closely-spaced parallel runways at Dubai International airport (Dubai, UAE (United Arab Emirates)); and iii) building the new additional runway(s) applied to the runway system of three London airports - Heathrow, Gatwick, and Stansted (London, UK).The results have shown that each of the considered solutions can contribute to more efficient and effective matching of the airport runway (landing) capacity to the current and expected (prospectively growing) airside demand under given (specified) conditions.     

税收优惠对企业研发投入的政策效应研究

研究目标：税收优惠对企业研发投入的政策效应。研究方法：以2015年深圳证券交易所上市公司（A股主板）的面板数据为基础,采用倾向得分匹配法（PSM）,并对比传统OLS回归方法,估计不同税收优惠方式对企业研发投入的政策效应。研究发现：税收优惠政策对企业研发投入量及企业研发投入强度具有激励作用,但研发费用加计扣除、研发费用加计扣除与税率优惠并用、税率优惠三种优惠方式,激励效应依次递减。研究创新：采用倾向得分法,将未享受税收优惠的企业作为享受税收优惠企业的“反事实”结果,对比分析税收优惠政策对样本产生的“净效应”。研究价值：根据当前我国企业特征,优化研发投入税收优惠政策。     

Worker heterogeneity and labor market volatility in matching models

Shimer demonstrated that aggregate productivity shocks in a standard matching model cause fluctuations in key labor market statistics—such as the job-finding rate, the vacancy/unemployment ratio, and the unemployment rate—that are too small by an order of magnitude [Shimer, R., 2005. The cyclical behavior of equilibrium unemployment and vacancies. American Economic Review 95 (1) 25–49]. This paper shows that when the standard model is extended to allow for worker heterogeneity, it exhibits considerably greater volatility. In the model, marginal workers, whose productivity only slightly exceeds the value of their alternative use of time, constitute a disproportionate share of unemployment on average, and that share rises when aggregate conditions deteriorate. These composition effects cause firms to open fewer vacancies during downturns.     

区域科技资源共享平台集成服务能力结构维度研究

随着我国全面实施创新驱动发展战略,科技资源共享平台已成为国家和地区集聚科技资源、创新服务需求的重要载体,培育和提升平台集成服务能力,是发挥科技资源共享平台创新服务支撑作用与杠杆效应的有效途径和战略选择。首先界定区域科技资源共享平台集成服务能力的内涵与特征,运用解释结构模型（ISM）对平台集成服务能力的关键要素及层次结构进行识别,进而选取广东、上海、北京和黑龙江等省市科技资源共享平台作为典型案例进行比较分析。结果表明,区域科技资源共享平台集成服务能力由资源集成能力、需求集成能力、服务匹配能力、运行管理能力4个维度构成,典型案例平台各有优势与特色,但在不同能力维度仍有提升空间。结论可为区域科技资源共享平台集成服务能力培育和提升提供理论方法指导,为区域科技资源共享平台更好地服务于战略性新兴产业创新和持续发展提供有效决策依据。     

Coexistence of long-term and short-term contracts

We study the length of agreements in a market in which infinitely-lived firms contract with agents that live for two periods. Firms differ in the expected values of their projects, as do workers in their abilities to manage projects. Worker effort is not contractible and worker ability is revealed during the relationship. The market dictates the trade-off between sorting and incentives. Short- and long-term contracts often coexist: The best firms always use short-term contracts to hire high-ability senior workers, firms with less profitable projects use short-term contracts to save on the cost of hiring junior workers, whereas intermediate firms use long-term agreements to provide better incentives to their workers. We relate our results to the optimal assignment literature that follows Becker (1973).     

移动支付因素对现金供应的量化影响研究——基于倾向评分匹配的经济金融变量影响关系探讨

现金作为现阶段我国基础货币供应量中最活跃部分,是反映经济金融基本运行形势的重要指标。本文运用倾向评分匹配和向量自回归方法,研究对现金供应量产生显著影响的相关经济金融因素,量化探讨与判别各因素间的相互因果关系和长期均衡关系,并使用重庆区域2011-2020年各类经济金融数据进行实证检验。研究发现:移动支付对现金供应具有明显的替代效应,国内生产总值、工业增加值、社会消费品零售额和住户存款等指标对移动支付替代效应具有持续影响;国内生产总值和社会消费品零售额均对现金的投放回笼具有明显的正向因果关系。最后,本文从货币当局的角度提出相应政策建议。     

International collaboration and innovation: Evidence from a leading Chinese multinational enterprise

This paper investigates the impact of international collaboration and its characteristics on the quality of the innovation of multinational enterprises (MNEs) in emerging markets. Using a unique dataset of 1428 international and comparable domestic collaboration projects over the 2010–2016 period, it finds that while international innovation collaborations are associated with high innovation quality, cultural distance has a negative effect on collaboration outcomes. Moreover, proximity to the focal firm's overseas R&D centres and the size of expenditure budgets play significant moderating roles in overcoming cultural barriers. Based on the RBV and dynamic capabilities theory, we investigate how firms from emerging markets can acquire these two crucial requisites for innovation. The characteristics of partners and intellectual property (IP) arrangements are also found to have a significant impact on the quality of innovations.