公平与效率关系的再思考

公平已成为当代中国的热点问题。市场经济是科学认识公平与效率关系的逻辑起点。而市场扭曲和政府错位是目前社会公平陷于困境的主要原因。只有当政府和企业各司其职 ,也就是政府致力于公平 ,企业专注于效率时 ,公平和效率的冲突才能得到有效缓解     

完善我国合同法应借鉴《国际商事合同通则》

1999年10月1日后正式实施的《中华人民共和国合同法》已经借鉴了当今发达国家先进的合同法立法经验和国际惯例,但与其它国家和有关国际公约的立法相比较,若干条文和规定仍然是粗线条的。文章以《国际商事合同通则》为例与我国合同法对比,探讨了我国合同立法在合同的成立、合同效力问题、精神损害赔偿、“意外条款”的效力、合同的解释等方面的一些缺陷,以期对我国合同法的完善有所借鉴。     

Empirical likelihood confidence intervals for the mean of a population containing many zero values

If a population contains many zero values and the sample size is not very large, the traditional normal approximation‐based confidence intervals for the population mean may have poor coverage probabilities. This problem is substantially reduced by constructing parametric likelihood ratio intervals when an appropriate mixture model can be found. In the context of survey sampling, however, there is a general preference for making minimal assumptions about the population under study. The authors have therefore investigated the coverage properties of nonparametric empirical likelihood confidence intervals for the population mean. They show that under a variety of hypothetical populations, these intervals often outperformed parametric likelihood intervals by having more balanced coverage rates and larger lower bounds. The authors illustrate their methodology using data from the Canadian Labour Force Survey for the year 2000.     

GMM tests for the Katz family of distributions

Generalized method of moments (GMM) is used to develop tests for discriminating discrete distributions among the two-parameter family of Katz distributions. Relationships involving moments are exploited to obtain identifying and over-identifying restrictions. The asymptotic relative efficiencies of tests based on GMM are analyzed using the local power approach and the approximate Bahadur efficiency. The paper also gives results of Monte Carlo experiments designed to check the validity of the theoretical findings and to shed light on the small sample properties of the proposed tests. Extensions of the results to compound Poisson alternative hypotheses are discussed.     

A Note on the Role of the Propensity Score for Estimating Average Treatment Effects

Hahn [Hahn, J. (1998). On the role of the propensity score in efficient semiparametric estimation of average treatment effects. Econometrica 66:315-331] derived the semiparametric efficiency bounds for estimating the average treatment effect (ATE) and the average treatment effect on the treated (ATET). The variance of ATET depends on whether the propensity score is known or unknown. Hahn attributes this to “dimension reduction.” In this paper, an alternative explanation is given: Knowledge of the propensity score improves upon the estimation of the distribution of the confounding variables.     

英语写作中有效反馈信息的探讨

文章简要阐述了反馈信息,论述了作文工作研究的意义及在作文写作中有效的信息反馈形式,提出了增强写作能力的可行措施。     

诉讼中的对抗与合作

诉讼对抗是诉讼的结构性因素，诉讼当事人的双方被置于相互对立、相互抗争的地位上并展开攻击和防御活动，以发现案件真实。对抗的弊端是：过度对抗引起诉讼拖延，对抗加大了诉讼成本，对抗发现真实功能的发挥越来越有限。近年来，诉讼合作迅速兴起，有利于兼顾当事人各方的利益，提高诉讼效率，节约诉讼成本，促进和谐社会的形成。坚持诉讼对抗与诉讼合作并重，是我国司法改革的方向。     

双波长比值法测定氯硝基苯异构体的含量

依据邻、间、对氯硝基苯三组分的比值光谱特征，以间氟硝基苯为参比组分，选择219nm、232nm和244nm、297nm作为邻氯硝基苯和对氯硝基苯的测定波长；以对氯硝基苯为参比组分．选择253nm、325nm作为间氟硝基苯的测定波长．测定邻、间、对氯硝基苯混合样品中三组分含量，结果显示。邻氯硝基苯在（3．73～74．34）mg／L，间氯硝基苯在（1．58～105．1）mg／L，对氯硝基苯在（0．36-107．1）mg／L范围具有良好的线性关系．回收率均在95．0％～110．0％之间．本法具有测定波长少、计算简单、光谱“分离”能力强。易于推广等特点．     

提高网络环境下的检索效率

围绕查全率、查准率这两个重要指标对网络环境下影响检索效率的因素进行了分析,提出提高网络环境下检索效率的一些方法,以便更好地服务于用户.     

Adaptive tests of regression functions via multiscale generalized likelihood ratios

Many applications of nonparametric tests based on curve estimation involve selecting a smoothing parameter. The author proposes an adaptive test that combines several generalized likelihood ratio tests in order to get power performance nearly equal to whichever of the component tests is best. She derives the asymptotic joint distribution of the component tests and that of the proposed test under the null hypothesis. She also develops a simple method of selecting the smoothing parameters for the proposed test and presents two approximate methods for obtaining its P‐value. Finally, she evaluates the proposed test through simulations and illustrates its application to a set of real data.