Practical procedures to deal with common support problems in matching estimation

This paper assesses the performance of common estimators adjusting for differences in covariates, such as matching and regression, when faced with the so-called common support problems. It also shows how different procedures suggested in the literature affect the properties of such estimators. Based on an empirical Monte Carlo simulation design, a lack of common support is found to increase the root-mean-squared error of all investigated parametric and semiparametric estimators. Dropping observations that are off support usually improves their performance, although the magnitude of the improvement depends on the particular method used.     

土地流转中为什么会形成大量小农复制

土地流转是实现规模化经营的前提之一,然而土地流转中却出现大量小农复制,从而影响土地流转的质量和效果。运用12省(自治区)2 553份农户问卷,详细分析土地流转中小农复制的现状及其形成原因。研究发现：(1)农户流转耕地面积不大,转入户流转面积20亩及以下的约占总转入户数的60.3％,转出户流转面积5亩及以下的约占总转出户数的74.38％,转出户中仍然经营土地的约占总转出户数的74％。(2)农业分工发达使生产更加方便、文化传统形成路径依赖、禀赋效应产生“价值幻觉”以及公共服务不健全使未来存在不确定性导致转出户流转部分土地。乡土社会限制土地流转范围和经营风险增加风险感知导致转入户流转小规模土地。     

Information and communication technology adoption in micro and small firms: Can internet access improve labour productivity?

The rapid spread of information and communication technologies (ICT) may increase firms’ productivity with important consequences for job creation and for economic growth. This article contributes to this discussion by analysing the impact of internet adoption on labour productivity and the mechanisms shaping this relationship in Peruvian micro and small manufacturing firms over the period 2011–2013. The article estimates a reduced form where labour productivity is a function of internet adoption and other explanatory factors. Internet adoption is instrumented using a measure of the availability of financial opportunities for micro and small firms in Peru. Findings indicate that internet adoption: (a) increases firms’ labour productivity; (b) reallocates employment away from temporary administrative workers and non‐remunerated workers and expands employment of permanent production workers; (c) leads to the formalization of labour relationships, to the implementation of new organizational practices and to the improvement of training measures. While changes in employment and formalization of workers are linked to labour productivity gains, increases in training measures and organizational changes do not generate any additional productivity increase. Policies oriented to promote the adoption of ICT in micro and small firms can be beneficial to close the productivity gap with larger firms in Peru. Moreover, policies directed to the formalization of the workforce can provide an extra benefit, i.e. additional labour productivity gains in firms adopting the internet. Finally, policies oriented to the development of digital skills are also important to ease the re‐employment of those workers losing their jobs and the achievement of additional productivity gains that new organizational practices can provide.     

全域旅游视角下的天府旅游名县竞争力研究——以四川省县域城市为例

天府旅游名县创建是按照全域旅游发展理念开展的，以建设世界重要旅游目的地为目标的建设工程。文章在系统整理旅游目的地竞争力主要研究成果基础上，建立15个天府旅游名县竞争力评价指标，基于可量化数据，采用主成分和聚类分析方法，对进入天府旅游名县的40个县(市、区）进行实证研究。结果显示，旅游核心竞争力、旅游发展规模、旅游综合实力、非优势资源品牌创建能力等因素是构成天府旅游名县评判的主要因子；从空间结构上看，呈现成都平原最强，川西、川北居中，川南最弱的局面；从创建动力上看，不应仅关注创建结果，而应通过创建工作，促进县域经济综合发展水平和城市发展潜力提升。     

Supply chain agility as an acclimatisation process to environmental uncertainty and organisational vulnerabilities: insights from British SMEs

Abstract

Even though supply chain agility (SCA) has been considered an essential concept in supply chain management (SCM) research, the way it is experienced and manifested, especially by small and medium-sized enterprises (SMEs), has received much less attention. Our purpose is to focus on SME organisational vulnerabilities in the context of increased environmental uncertainty, and explore how SCA is developed and applied by SMEs amid their vulnerabilities. By relying on insights from comparative case studies of three British SMEs, we examine SME SCA as an acclimatisation process and delve into SMEs’ experiences of facing environmental uncertainty while developing and applying SCA. Our findings highlight that organisational attitudes underlie how SMEs perceive environmental uncertainty, tackle organisational vulnerabilities and develop SCA as an acclimatisation process. Our findings also reveal that resource constraints, supply chain relationships, interorganisational power dynamics, and access to information play important roles in developing SCA.     

陕西省小城镇发展模式研究

从"城镇空间组织关系"、"区域自然生态条件"、"城镇发展水平"三个维度出发进行综合空间分类,大致可把陕西省小城镇分为中心城市带动型、自组织发展型、落后地区引导发展型三种类型,并在发展模式选择与实施等方面做了探讨,为政府决策提供政策参考。     

Generating synthetic data to produce public-use microdata for small geographic areas based on complex sample survey data with application to the National Health Interview Survey

Small area statistics obtained from sample survey data provide a critical source of information used to study health, economic, and sociological trends. However, most large-scale sample surveys are not designed for the purpose of producing small area statistics. Moreover, data disseminators are prevented from releasing public-use microdata for small geographic areas for disclosure reasons; thus, limiting the utility of the data they collect. This research evaluates a synthetic data method, intended for data disseminators, for releasing public-use microdata for small geographic areas based on complex sample survey data. The method replaces all observed survey values with synthetic (or imputed) values generated from a hierarchical Bayesian model that explicitly accounts for complex sample design features, including stratification, clustering, and sampling weights. The method is applied to restricted microdata from the National Health Interview Survey and synthetic data are generated for both sampled and non-sampled small areas. The analytic validity of the resulting small area inferences is assessed by direct comparison with the actual data, a simulation study, and a cross-validation study.     

Linguistic practice and identity work: Variation in Taiwan Mandarin at a Taipei County high school

This article examines variation in the use of two Taiwan Mandarin features, de‐retroflection of sibilant fricatives [?] → [s], and labial glide deletion [w?] → [?], in the speech of Taipei County high school students. The features become resources for the negotiation of identity positions within the highly structured school institution. I discuss the correlations between the use of Taiwan Mandarin and two social factors: membership in the small culture (Holliday 1999 ) of a particular bānjí or class, and individual aspirations. Holliday's concept of small cultures is proposed as a variant of the Community of Practice. I refer to Bucholtz and Hall's ( 2004 ) tactics of intersubjectivity framework as a possible tool for explaining variation at the school. I argue that the two Taiwan Mandarin features are invoked to perform different social goals, which is possible because they are imbued with related but significantly different sociocultural meanings (Brubaker 2012 ; Baran 2007 ).     

Optimal cut-off for rare events and unbalanced misclassification costs

This paper develops a method for handling two-class classification problems with highly unbalanced class sizes and misclassification costs. When the class sizes are highly unbalanced and the minority class represents a rare event, conventional classification methods tend to strongly favour the majority class, resulting in very low detection of the minority class. A method is proposed to determine the optimal cut-off for asymmetric misclassification costs and for unbalanced class sizes. Monte Carlo simulations show that this proposal performs better than the method based on the notion of classification accuracy. Finally, the proposed method is applied to empirical data on Italian small and medium enterprises to classify them into default and non-default groups.     

浙江农村青年创业小额贷款项目在基层的实施效果研究———以乐清市为例

浙江农村青年创业小额贷款项目自推出以来受到浙江基层创业青年广泛关注,该项小额贷款制度申请程序简便、担保形式灵活、政府扶持力度逐年加大,已逐步发展成为基层创业青年融资的主要途径之一.近年来,在浙江“两创”总战略鼓励下,农村青年创业小额贷款项目发展前景广阔、发展势头良好,同时在担保、风险控制、贷款覆盖面等方面也不乏矛盾和困惑