Intersection Bounds: Estimation and Inference

We develop a practical and novel method for inference on intersection bounds, namely bounds defined by either the infimum or supremum of a parametric or nonparametric function, or, equivalently, the value of a linear programming problem with a potentially infinite constraint set. We show that many bounds characterizations in econometrics, for instance bounds on parameters under conditional moment inequalities, can be formulated as intersection bounds. Our approach is especially convenient for models comprised of a continuum of inequalities that are separable in parameters, and also applies to models with inequalities that are nonseparable in parameters. Since analog estimators for intersection bounds can be severely biased in finite samples, routinely underestimating the size of the identified set, we also offer a median‐bias‐corrected estimator of such bounds as a by‐product of our inferential procedures. We develop theory for large sample inference based on the strong approximation of a sequence of series or kernel‐based empirical processes by a sequence of “penultimate” Gaussian processes. These penultimate processes are generally not weakly convergent, and thus are non‐Donsker. Our theoretical results establish that we can nonetheless perform asymptotically valid inference based on these processes. Our construction also provides new adaptive inequality/moment selection methods. We provide conditions for the use of nonparametric kernel and series estimators, including a novel result that establishes strong approximation for any general series estimator admitting linearization, which may be of independent interest.     

Some inverse min-max network problems under weighted l1 and l∞ norms with bound constraints on changes

We consider some inverse min-max (or max-min) network problems. Such an inverse problem is to modify the weights with bound constraints so that a given feasible solution becomes an optimal solution of a min-max (or max-min) network problem, and the deviation of the weights, measured by the weighted l ₁ norm or weighted l _∞ norm, is minimum. In this paper, we present strongly polynomial time algorithms to solve the inverse min-max spanning tree problem and the inverse maximum capacity path problem.     

生产率、资本密集度对企业国际化模式选择决策的影响

加入WTO以来,中国在全球贸易中占据了举足轻重的地位,其中出口、对外投资是中国企业国际化的主要模式。为了考察企业生产率与资本密集度对国际化模式选择的影响,本文利用2005-2007年《中国工业企业数据库》和《境外投资企业（机构）名录》,按非出口、仅出口、仅投资和既出口又投资将全部企业划分为四种国际市场参与模式,使用多值Logit模型及相对风险概率对企业国际化模式选择进行检验。结果表明：较高生产率的企业更可能选择对外投资;劳动密集型企业更可能出口,资本密集型企业更可能对外投资;不同地区企业的生产率与资本密集度对企业国际化模式选择的影响具有差异。最后本文进一步从对外投资经营形式角度对对外直接投资的“引致出口效应”进行了解释。     

中国对外直接投资对国内产业升级的作用机理--基于不同投资动机的探讨

近年来中国对外直接投资快速发展,其与国内产业升级的互动关系已经成为学术界研究的一个重点问题。根据企业投资动机的不同,中国对外直接投资可以分为资源寻求型、效率寻求型、市场寻求型及战略资源寻求型等类别,且不同类别的对外直接投资通过不尽相同的直接或间接路径影响国内产业升级,如保障关键资源供给、推动低端产业转移、扩大市场规模、提高技术管理水平等。但总体来看,对上述影响路径的分析较为零散,缺乏明晰体系。在全面提升开放型经济水平新形势下,系统梳理和深入解析多元动机下中国对外直接投资对国内产业升级的作用机理至关重要。     

International Student Exchange in Australian Social Work Education

International student exchange is pursued by Australian schools of social work as a strategy to engage with the internationalisation agenda set by government, universities, and the profession. However, little concrete information about the nature and scope of these activities exists. The study reported here aimed to address this gap. Twenty-seven of the 30 Australian universities that offer social work programs participated in an online survey about international student exchange activities. The results indicate that a majority of schools (n?=?23) do engage in such activities, with international field placements the most frequent form of exchange. Exchanges are most likely to be facilitated and managed by social work staff. The findings, and their implications for the development of good practice in international student exchange, are discussed. This research provides a “point-in-time” snapshot of international exchange in Australian social work education and a benchmark for future analyses of this expanding practice in the profession.     

关于《归去来兮辞》的几个问题

陶渊明诗文辞赋145篇,从古至今存在许多疑难问题。而且在研究过程中,由于理解的不同,不断滋生新的问题。动荡时代往往把陶渊明看作政治诗人,升平时代则视为休闲诗人。由此派生出不少新的问题。如《归去来兮辞》的有事、巾车、孤舟,本无深意,然时下论者却提出了别有寓意的新解。但反复审视,似乎值得再作考虑。     

国际GFP统计规则调整对中国经常账户的影响

2008年IMF发布的《国际收支与国际投资手册》（第六版）对国际加工贸易（Goods for Processing,GFP）中的项目统计进行了调整。由于我国对外贸易中GFP所占的比重较高,因此此次调整对我国国际收支平衡表中的经常项目将产生较大影响。本文通过对GFP几种主要类型的分析,探讨了这种调整分别对我国经常项目统计产生的影响。     

OFDI对中国国际收支影响的机理与实际测算

国际直接投资不仅会影响东道国国际收支,也会对投资母国国际收支产生影响。本文重点分析了对外直接投资对母国国际收支的影响机制,并构建了对外直接投资对母国国际收支影响的数理分析框架,研究表明对外直接投资通过投资效应、利润汇回效应和贸易效应所包含的七个渠道影响母国国际收支;对外直接投资初期会造成母国国际收支净效应为负的情形,但伴随对外直接投资存量的累积,国际收支净效应会逐步为正。最后本文测算了中国对外直接投资对其国际收支的影响,结果表明中国对外直接投资收益率大于国内投资收益率;近年来国际收支净效应持续为负,但对改善 “双顺差”模式起到了积极作用。     

中国企业对外直接投资的出口效应——基于企业异质性视角的经验研究

本文使用2000-2007年中国境外投资企业（机构）名录和中国工业企业数据库的匹配数据,从企业异质性视角出发,给出了对外直接投资影响商品出口的经验证据。研究发现,我国企业对外直接投资总体促进了出口,但促进作用在异质性视角下存在明显差异。具体而言：①对外直接投资显著促进了中间品和消费品出口,对资本品出口的影响不确定;②水平型对外直接投资对商品出口的促进作用强于垂直型对外直接投资对商品出口的促进作用;③水平型对外直接投资对中间品和消费品出口均有显著的促进作用,对资本品出口的影响不确定,垂直型对外直接投资对中间品、消费品和资本品出口的影响均不确定;④水平型对外直接投资对劳动密集型、资本密集型和技术密集型商品出口均有显著的促进作用,垂直型对外直接投资对资本密集型和技术密集型商品出口均有显著的促进作用,对劳动密集型商品出口的影响不确定;⑤企业生产效率的提升,一定程度抑制了垂直型对外直接投资对出口的促进作用。     

中国对外直接投资的机遇、风险与安全对策——以发达国家主权债务危机为视域

近年来,主权债务危机自二战结束以来第一次在发达国家群体内成规模地爆发。其通过东道国政府间接征用和市场需求萎缩、银行业危机等新渠道影响该地区内正处于迅速上升期的中国直接投资,给我国企业带来机遇和风险并存的外部环境。文章在分析我国在发达地区直接投资现状与特点及建立发达国家主权债务危机与国际直接投资相互作用分析框架的基础上,具体讨论源于我国不同投资者、以不同模式进入发达国家不同行业的直接投资受到的不同程度与性质的影响,并对我国企业在发达国家主权债务危机背景下开展直接投资活动提出相关建议。