农村人力资本投资视阈下的地方农业高校作为

农村人力资本是一种提供未来经济价值的资本。新农村建设对农村人力资本的培育提出了更高的要求。地方农业高校处于中心城市的区位优势,加之长久服务三农的经验及得天独厚的信息、人才、科技优势决定了其在农村人力资本的投资中应积极作为:建立农村劳动力培训体系,探索各形式的科技推广服务,并致力于学习型农村的构建,提升农村人力资本的学习能力与科技素质,为新农村建设提供强有力的智力支持与人才支撑。     

Tracing ‘driver’ versus ‘modulator’ information flow throughout large-scale,task-related neural circuitry

Primary objective: To determine the relative uses of neural action potential (‘spike’) data versus local field potentials (LFPs) for modeling information flow through complex brain networks. Hypothesis: The common use of LFP data, which are continuous and therefore more mathematically suited for spectral information-flow modeling techniques such as Granger causality analysis, can lead to spurious inferences about whether a given brain area ‘drives’ the spiking in a downstream area. Experiment: We recorded spikes and LFPs from the forelimb motor cortex (M1) and the magnocellular red nucleus (mRN), which receives axon collaterals from M1 projection cells onto its distal dendrites, but not onto its perisomatic regions, as rats performed a skilled reaching task. Results and implications: As predicted, Granger causality analysis on the LFPs—which are mainly composed of vector-summed dendritic currents—produced results that if conventionally interpreted would suggest that the M1 cells drove spike firing in the mRN, whereas analyses of spiking in the two recorded regions revealed no significant correlations. These results suggest that mathematical models of information flow should treat the sampled dendritic activity as more likely to reflect intrinsic dendritic and input-related processing in neural networks, whereas spikes are more likely to provide information about the output of neural network processing.     

选择神祗:明代公祀体系的包容与排斥——以地方公祭神祠为中心

明代地方公祭内容当中,各类神祗祭祀的变化最为频繁,大致经历了洪武朝定制期,成化、弘治迅速发展期,以及嘉靖以后的持续增长期三个阶段,祭祀内容不断增加,以致繁复.地方公祭对象的选择标准主要考虑其是否有功于国家、惠爱在民、具有保佑功能,或学识德行昭著.这样的选择标准是基于对公共利益的考量,即通过对这些神祗的公祭,发挥崇德报功、示范表率,及舆论导向的功用.因此,明代公祀体系具有明显的“为公”属性.整体来看,明代地方公祀体系是开放的,并处于不断变动中,其包容和排斥性构成理解明代地方祭祀信仰层级结构的一个视角.这种层级结构显示出明朝政府对国家所倡导的儒家信仰、制度性的宗教信仰,以及各类民间信仰的基本态度.     

论万历《顺天府志》的体例纂修特点与文献价值

万历《顺天府志》是北京历史上第一部保存完整的府志,也是现存最完整的一部明代官修北京志书,具有重要的文献价值。作者从分析其体例结构和纂修特点入手,将它与清人纂修的康熙、光绪《顺天府志》和乾隆《日下旧闻考》作了基本比较,指出志书究竟是篇幅宏大好还是简明扼要好,何为质量上乘的精品佳志,不能一概而论,要作系统研究和具体分析,认为从版本学、方志学、文献学和历史研究而言,万历《顺天府志》都具有不可或缺的重要意义。     

Asymptotic normality of the local linear estimation of the conditional density for functional time-series data

This article focuses on the conditional density of a scalar response variable given a random variable taking values in a semimetric space. The local linear estimators of the conditional density and its derivative are considered. It is assumed that the observations form a stationary α-mixing sequence. Under some regularity conditions, the joint asymptotic normality of the estimators of the conditional density and its derivative is established. The result confirms the prospect in Rachdi et al. (2014 Rachdi, M., A. Laksaci, J. Demongeot, A. Abdali, and F. Madani. 2014. Theoretical and practical aspects of the quadratic error in the local linear estimation of the conditional density for functional data. Computational Statistics and Data Analysis 73 :53–68.[Crossref], [Web of Science ®] , [Google Scholar]) and can be applied in time-series analysis to make predictions and build confidence intervals. The finite-sample behavior of the estimator is investigated by simulations as well.     

On the Use of GLS Demeaning in Panel Unit Root Testing

One of the most well-known facts about unit root testing in time series is that the Dickey–Fuller (DF) test based on ordinary least squares (OLS) demeaned data suffers from low power, and that the use of generalized least squares (GLS) demeaning can lead to substantial power gains. Of course, this development has not gone unnoticed in the panel unit root literature. However, while the potential of using GLS demeaning is widely recognized, oddly enough, there are still no theoretical results available to facilitate a formal analysis of such demeaning in the panel data context. The present article can be seen as a reaction to this. The purpose is to evaluate the effect of GLS demeaning when used in conjuncture with the pooled OLS t-test for a unit root, resulting in a panel analog of the time series DF–GLS test. A key finding is that the success of GLS depend critically on the order in which the dependent variable is demeaned and first-differenced. If the variable is demeaned prior to taking first-differences, power is maximized by using GLS demeaning, whereas if the differencing is done first, then OLS demeaning is preferred. Furthermore, even if the former demeaning approach is used, such that GLS is preferred, the asymptotic distribution of the resulting test is independent of the tuning parameters that characterize the local alternative under which the demeaning performed. Hence, the demeaning can just as well be performed under the unit root null hypothesis. In this sense, GLS demeaning under the local alternative is redundant.     

中国地方政府债务的结构性风险

在或有债务不确定触发地方政府代偿的现实背景下,本文对地方政府显性债务和或有债务的结构性风险进行了模型刻画,给出了两类债务违约概率的显示解及其估计方法。基于地方政府报告的显性债务和审计署的有关公告等,本文对地方政府的显性债务和或有债务规模进行了结构性分解和估算,多视角估计了不同久期（或平均债务到期时间）下的两类债务的结构性风险状态,同时对比分析了其变动趋势。模型估计表明：地方政府债务风险的主要形态是或有债务的不确定触发,在部分时段内,地方政府的结构性代偿压力明显较大,但债券置换等旨在拉长债务久期的政策设计有助于缓释地方政府债务的信用风险边界,降低地方政府的结构性代偿压力。本文用具体数字揭示了地方政府债务的结构性风险状况及其变动趋势,以及地方政府债务久期之伸缩与其代偿压力之间的定量关系。     

住房价格、土地价格与地方政府行为

本文基于中国35个大中城市2005至2015年的面板数据,通过构建具有“空间依赖”性质的房价地价空间面板联立方程模型,深入研究房价与地价关系、地方政府行为对房价和地价的作用机制以及城际间的相互作用。研究表明,临近城市间的房价相互“模仿”并一同推动地价上涨,房价对地价的影响呈现“模仿促进”的作用特征;各城市通过尽可能抬高本地地价来拉大与临近城市地价水平的差距,进而推高房价,实现“以地生财”。此外,研究还证实地方政府通过“价格途径”和“政策途径”均能对房价进行有效调控,且“价格途径”具有一定的传染性;而“数量途径”和“结构途径”作为地方政府控制地价的有效手段,具有较强的溢出效应。     

Estimating the error distribution function in semiparametric additive regression models

We consider semiparametric additive regression models with a linear parametric part and a nonparametric part, both involving multivariate covariates. For the nonparametric part we assume two models. In the first, the regression function is unspecified and smooth; in the second, the regression function is additive with smooth components. Depending on the model, the regression curve is estimated by suitable least squares methods. The resulting residual-based empirical distribution function is shown to differ from the error-based empirical distribution function by an additive expression, up to a uniformly negligible remainder term. This result implies a functional central limit theorem for the residual-based empirical distribution function. It is used to test for normal errors.     

Local power properties of some asymptotic tests in symmetric linear regression models

In this paper we obtain asymptotic expansions, up to order n^−1/2 and under a sequence of Pitman alternatives, for the nonnull distribution functions of the likelihood ratio, Wald, score and gradient test statistics in the class of symmetric linear regression models. This is a wide class of models which encompasses the t model and several other symmetric distributions with longer-than normal tails. The asymptotic distributions of all four statistics are obtained for testing a subset of regression parameters. Furthermore, in order to compare the finite-sample performance of these tests in this class of models, Monte Carlo simulations are presented. An empirical application to a real data set is considered for illustrative purposes.