农机服务发展与粮食生产效率研究:2004—2016——基于变系数随机前沿分析

采用“两步法”研究了农机服务发展与中国粮食生产效率的关系.基于2004-2016年全国31省份粮食生产投入产出的面板数据,利用变系数随机前沿分析方法测算了中国粮食生产的技术变化、技术效率以及全要素生产率,然后构建农机服务发展影响粮食生产效率的OLS回归模型.结果表明:(1)31省份粮食生产的投入要素产出弹性和技术效率存在明显差异,2008年粮食技术变化最为明显,粮食全要素生产率的增长在2008年高达5%.(2)农机服务在2008年以后对粮食全要素生产率的增长具有显著的促进作用,农机服务对粮食TFP的作用存在一定的滞后效应.(3)农机服务发展与劳动产出弹性具有替代关系,与化肥和机械产出弹性具有互补关系.在三大粮食作物中,小麦机械化程度最高,水稻和玉米的机械化程度还有待提升.     

金融创新对货币政策传导的影响

货币政策要发挥作用,必须通过其传导机制来实现.金融创新的不断发展大大削弱了传统的货币政策传导机制的理论基础,使货币政策传导需要考虑的因素多元化,传导途径变得复杂化,基于此,提出了货币政策传导机制的分析框架,探讨了金融创新对货币政策传导渠道中的各个要素的影响,指出金融创新改变每种传导渠道的相对重要性,使货币政策传导同时受到加强和削弱的效果,即金融创新对货币政策传导的影响具有非平衡性.     

股指期货基于信息传递效应稳定作用的局限性

股指期货对现货市场的波动有潜在的影响。有学者认为股指期货能向现货市场传递信息,可提高信息质量,加快证券价格对新信息的反应速度,促进信息效率,从而起到稳定市场的作用。但是,股指期货信息传递效应对现货市场的稳定作用具有一定的局限性,这种局限性源于：第一,股指期货有限的价格发现功能;第二,股指期货有可能向现货市场传递有噪音信息;第三,市场解释信息方式影响稳定作用发挥的程度;第四,股指期货引起信息同质性,使市场丧失信念多样性,更易反应过度。     

Asymptotic distribution of regression correlation coefficient for Poisson regression model

This study treats an asymptotic distribution for measures of predictive power for generalized linear models (GLMs). We focus on the regression correlation coefficient (RCC) that is one of the measures of predictive power. The RCC, proposed by Zheng and Agresti is a population value and a generalization of the population value for the coefficient of determination. Therefore, the RCC is easy to interpret and familiar. Recently, Takahashi and Kurosawa provided an explicit form of the RCC and proposed a new RCC estimator for a Poisson regression model. They also showed the validity of the new estimator compared with other estimators. This study discusses the new statistical properties of the RCC for the Poisson regression model. Furthermore, we show an asymptotic normality of the RCC estimator.     

两组特殊标点符号的用法分析

为了防止或减少媒介因不当使用相关特殊标点符号而导致信息传播的质量下降，提高有关人员的写作或编辑质量，针对图书、期刊和报纸等出版物在使用标点符号“．”与“·”及“：”与“：”中出现的错误，利用典型例子，阐述了它们的常见用法，并对使用过程中易犯的一些错误进行了分析，提出了相关建议。     

Dynamics of the term structure of interest rates and monetary policy: is monetary policy effective during zero interest rate policy?

The monetary policy targets the short rates; however, during zero interest rate policy (ZIRP), the short end of the yield curve cannot serve as a policy instrument. Relying on the joint yields-macro latent factors model, this study empirically examines the effect of monetary policy stances on term structure and the possible feedback effect on the real sector using the Japanese experience of ZIRP. The analysis indicates that it is the entire term structure that transmits the policy shocks to the real economy rather than the yield spread only. The monetary policy signals pass through the yield curve level and slope factors to stimulate the economic activity. The curvature factor, besides reflecting the cyclical fluctuations of the economy, acts as a leading indicator for future inflation. In addition, policy influence tends to be low as the short end becomes segmented toward medium/long-term of the yield curve. Furthermore, volatility in bond markets is found to be asymmetrically affected by positive and negative shocks and long end tends to be less sensitive to stochastic shocks than the short maturities. The expectation hypothesis of the term structure does not hold during the ZIRP period.     

Stochastic correlation coefficient ensembles for variable selection

In this paper, we propose a novel Max-Relevance and Min-Common-Redundancy criterion for variable selection in linear models. Considering that the ensemble approach for variable selection has been proven to be quite effective in linear regression models, we construct a variable selection ensemble (VSE) by combining the presented stochastic correlation coefficient algorithm with a stochastic stepwise algorithm. We conduct extensive experimental comparison of our algorithm and other methods using two simulation studies and four real-life data sets. The results confirm that the proposed VSE leads to promising improvement on variable selection and regression accuracy.     

后现代语境下跨文化传播的“图像转向”——蔡志忠漫画中英文版《论语》的启示

《论语》在其产生后的两千多年历史中,对中国、亚洲乃至世界政治、经济、文化、社会等各个层面都产生了深刻的影响。《论语》在其复译过程中产生了逾四十本风格迥异的译本,其中蔡志忠漫画中英文版《论语》为经典阐释开辟了一条新的道路。蔡版《论语》把作为一本充满东方气韵的古代哲思语录《论语》从独一无二或少数人特权的局限中解放出来,使之成为兼具民族个性及大众欢迎的文化产品,引发出我们对跨文化传播的思考。     

Pooled Cross-Sectional and Time Series Data: A Survey of Current Statistical Methodology

A data base that provides a multivariate statistical history for each of a number of individual entities is called a pooled cross-sectional and time series data base in the econometrics literature. In marketing and survey literature the terms panel data or longitudinal data are often used. In management science a convenient term might be management data base. Such a data base provides a particularly rich environment for statistical analysis. This article reviews methods for estimating multivariate relationships particular to each individual entity and for summarizing these relationships for a number of individuals. Inference to a larger population when the data base is viewed as a sample is also considered.     

Tables of the exact quantiles of the top-down correlation coefficient for n - 3(1)14

Iman and Connver (1985, 1987) have suggested the top-down correlation coefficient as a measure of association when n objects are ranked by two or more independent sources and interest centers primarily on agreement in the top rankings, with disagreements on items at the bottom of the rankings being of little or no importance. The top-down correlation coefficient results from computing the ordinary Pearson correlation coefficient on Savage scores. Quantiles of the exact distribution of the top-down correlation coefficient based on the assumption of independent rankings are provided for n = 3(1)14.