依赖与脆弱性：农民养老问题的一个实证分析——基于全国十个省份1000余位农民的调查数据

文章基于2009年全国十个省份30个行政村1000余位农民的调查数据，从“依赖性一脆弱性一养老困境”的逻辑关系出发．以农民养老的经济依赖途径为切入点。利用Multinomial Logistic回归模型，实证分析了农民养老的脆弱性及其影响因素。结果显示，那些同时具备女性、年龄较大、养儿防老观念比较强、家庭收入比较低、没有儿子、家庭整劳力比较少、纯农户和所在村经济情况比较差特征的农民，是依赖性最强的农民，他们面临的养老脆弱性程度也最高。由于现实生活中。全部具备上述所有条件的农民毕竟是少数。但农村社会政策刺定部门可以根据农民满足上述条件的多寡．来判断其养老脆弱性程度的高低。并以此为依据选择农村社会政策的重点关注对象。     

Robust methods in econometrics

This survey of recent developments in robust estimation and inference is directed primarily toward econometricians. It is argued that many of the techniques in common use in econometrics are highly sensitive to unverified hypotheses. Recent progress in designing alternative robust procedures is described and some prospects for future developments are discussed.     

关于魏晋时期自然观的形成和对中国绘画影响的研究

魏晋南北朝时期是中国历史上一个在政治、经济、文化等领域产生大变革的特殊时期,随着整个社会的重大转折,人的文化意识形态也会随之改变,玄学是当时社会意识形态转变的主要理论之一,它对中国文化中自然观念的形成有着极大的催化作用。同时,也对中国山水画的开端和发展有着重要的影响,这使处在萌芽状态中的中国山水画完全脱离了以前只作为人物画背景的状况。     

Robust estimation for ordinal regression

Ordinal regression is used for modelling an ordinal response variable as a function of some explanatory variables. The classical technique for estimating the unknown parameters of this model is Maximum Likelihood (ML). The lack of robustness of this estimator is formally shown by deriving its breakdown point and its influence function. To robustify the procedure, a weighting step is added to the Maximum Likelihood estimator, yielding an estimator with bounded influence function. We also show that the loss in efficiency due to the weighting step remains limited. A diagnostic plot based on the Weighted Maximum Likelihood estimator allows to detect outliers of different types in a single plot.     

Biased Bootstrap Methods for Reducing the Effects of Contamination

Contamination of a sampled distribution, for example by a heavy-tailed distribution, can degrade the performance of a statistical estimator. We suggest a general approach to alleviating this problem, using a version of the weighted bootstrap. The idea is to 'tilt' away from the contaminated distribution by a given (but arbitrary) amount, in a direction that minimizes a measure of the new distribution's dispersion. This theoretical proposal has a simple empirical version, which results in each data value being assigned a weight according to an assessment of its influence on dispersion. Importantly, distance can be measured directly in terms of the likely level of contamination, without reference to an empirical measure of scale. This makes the procedure particularly attractive for use in multivariate problems. It has several forms, depending on the definitions taken for dispersion and for distance between distributions. Examples of dispersion measures include variance and generalizations based on high order moments. Practicable measures of the distance between distributions may be based on power divergence, which includes Hellinger and Kullback–Leibler distances. The resulting location estimator has a smooth, redescending influence curve and appears to avoid computational difficulties that are typically associated with redescending estimators. Its breakdown point can be located at any desired value ε∈ (0, ½) simply by 'trimming' to a known distance (depending only on ε and the choice of distance measure) from the empirical distribution. The estimator has an affine equivariant multivariate form. Further, the general method is applicable to a range of statistical problems, including regression.     

论钱大昕的儒者品格

钱大昕是杰出的经学家和史学家,他力排“二氏”,专主儒学,深受儒家思想的浸染,形成了教人为善、立言不朽、修身修己等独特的儒者品格,这些品格是他为官、治学、做人的推动力和价值标准。钱大昕对儒学的专一来自于其治学、家庭、时代以及儒家思想文化主导地位的影响。     

我国粮食生产函数与影响因素分析

利用1978-2005年的相关数据建立粮食生产函数,并以此为基础来探讨影响我国粮食产量的主要因素。研究得出:农业劳动力作为粮食核心要素的地位不会改变;播种面积是影响粮食产量的关键要素;农用化肥仍然是粮食生产物质投入最重要的要素;灌溉面积和农业机械对粮食生产的影响不明显;农村用电量并未能提高粮食产量,相反可能存在一定的替代效用;自然灾害仍然是粮食减产的主要因素;家庭年产承包责任制并非仅仅是"一次性"的效应,农业劳动力的输出和转移也未产生明显的负效应。     

论明代中后期的鬻牒度僧

明代中期以后,实行鬻牒度僧。景泰、天顺年间,是鬻牒度僧初行时期;成化至正德年间,是鬻牒度僧基本确立时期。嘉靖以后,是鬻牒度僧普遍推行时期。户部及督抚等官是鬻牒度僧的主要倡议和推动者,礼部及僧录司等官开始多反对鬻牒,至正德以后也转而同意,而皇帝则可分为拒绝型、摇摆型、坚持型三类。明代中后期的鬻牒度僧,一定程度上缓解了财政危机,对巩固国防、保障百姓生活有一定积极意义;大量鬻牒度僧,使僧团冗滥混杂,对生产发展、社会稳定也起了阻碍作用;它与试度共同造就了明朝庞大的僧团,维系着佛教表面的繁盛;大量鬻牒度僧,导致僧众素质低下,佛学进一步衰微。对于明代社会来说,鬻牒度僧的积极意义是主要的;对于佛教来说,其消极作用更大。     

阴山文化对当代包头的影响

阴山文化是阴山区域形成的文化,具有远古性、草原性、民族性、融合性的文化特征,是阴山地理生态、生产方式、人文历史、民俗心理的综合。包头境内具有丰富的阴山文化历史资源,因此包头树立阴山文化的品牌最有优势。阴山文化可以准确揭示包头文化的特点,促进包头先进文化的建设,整合包头历史文化资源,培养市民素质,为建设文化大市奠定深厚的基础,促进包头文化产业的发展。     

现代科技与信息化浪潮对大学生的影响及对策

面向 2 1世纪的现代科技与信息化浪潮正向我们走来。我们必须从实际出发 ,充分发挥学生教育和管理工作的作用 ,正视网络工作阵地。教育学生刻苦学习 ,加强修养 ,抓住网络和信息技术革命的历史机遇 ,善于利用计算机与互联网络获取知识和信息 ,从而培养适应信息化浪潮的高素质人才