How non-normality affects the quadratic discriminant function

The quadratic discriminant function is commonly used for the two group classification problem when the covariance matrices in the two populations are substantially unequal. This procedure is optimal when both populations are multivariate normal with known means and covariance matrices. This study examined the robustness of the QDF to non-normality. Sampling experiments were conducted to estimate expected actual error rates for the QDF when sampling from a variety of non-normal distributions. Results indicated that the QDF was robust to non-normality except when the distributions were highly skewed, in which case relatively large deviations from optimal were observed. In all cases studied the average probabilities of misclassification were relatively stable while the individual population error rates exhibited considerable variability.     

Combinatoric classification of multivariate normal variates

Consider classifying an n × I observation vector as coming from one of two multivariate normal distributions which differ both in mean vectors and covariance matrices. A class of dis-crimination rules based upon n independent univariate discrim-inate functions is developed yielding exact misclassification probabilities when the population parameters are known. An efficient search of this class to select the procedure with minimum expected misclassification is made by employing an algorithm of the implicit enumeration type used in integer programming. The procedure is applied to the classification of male twins as either monozygotic or dizygotic.     

英语边缘介词的探讨

英语界对摫咴到榇蕯的提法较模糊，尚无系统的阐述，文章通过对其定义、特点和分类进行较全面的分析，尤其是对边缘介词中最活跃的部分棗分词介词作了细致探讨，旨在唤起英语工作者和读者关注此类摫咴禂词的存在，并掌握英语边缘介词的使用规律．     

The macroeconomics of fertility in small open economies: A test of the Becker-Barro model for The Netherlands and New Zealand

Becker and Barro (1988) formulated a theoretical model which identified a range of macroeconomic variables which can temporarily or permanently affect fertility in small open economies. This article tests the Becker-Barro model with relevant data which covers most of the 20th century for two small open economies, namely The Netherlands and New Zealand. The results show that government subsidies for having children have a strong positive effect on fertility, while the provision of public pensions has a strong negative effect. The degree of intergenerational altruism appears to have been declining. Moreover, there is only weak support for the hypothesis that real interest rates positively influence fertility. Received: 2 March 1998/Accepted: 1 September 1999     

Age structure effects and growth in the OECD, 1950–1990

Economic growth depends on human resources and human needs. The demographic age structure shapes both of these factors. We study five-year data from the OECD countries 1950–1990 in the framework of an age structure augmented neoclassical growth model with gradual technical adjustment. The model performs well in both pooled and panel estimations. The growth patterns of GDP per worker (labor productivity) in the OECD countries are to a large extent explained by age structure changes. The 50–64 age group has a positive influence, and the group above 65 contributes negatively, while younger age groups have ambiguous effects. However, the mechanism behind these age effects is not yet resolved. Received: 16 January 1997/Accepted: 2 July 1998     

论税收学第一个理论体系的形成与历史价值

税收历史上的第一个学科理论体系是资产阶级在反对封建生产方式的斗争中,为了发展新的生产力的需要,由三位伟大的英国经济学家建立起来的。这个理论体系第一次系统地提出了关于税收性质、税收原则、税收分类等重要问题的最初科学看法。这些看法中的某些重要观点,对于我国建立中国特色社会主义的税收理论体系,仍具有重要的启迪和借鉴价值。     

论教学研究型大学科研与教学的互馈作用

文章重点分析了教学研究型大学中科研与教学的关系,论证了科研与教学是密不可分的,科研是教学工作的有力保障,是提高教师的教学水平和培养合格人才的必由之路,教学是科研工作的检验和有力的驱动力,是教师从事科研的驱动力。在激烈竞争的环境中,充分发挥好教学与科研的互馈作用是教学研究型大学得以生存、发展的保证。     

运营企业理念的分类及历史演变

提出了运营企业的新概念,简要区分了运营企业与企业管理、企业经营的区别,进而提出了运营企业的理念分类。分析了六种不同的理念,分析和阐述六种理念的核心观点和理论模型及在不同历史时期的不同表现,认为运营企业的理念处于不断的发展和演化过程中。     

On the power of durbin-watson statistic against fractionally integrated processes

This paper provides the theoretical explanation and Monte Carlo experiments of using a modified version of Durbin-Watson ( D W ) statistic to test an 1 ( 1 ) process against I ( d ) alternatives, that is, integrated process of order d, where d is a fractional number. We provide the exact order of magnitude of the modified D W test when the data generating process is an I ( d ) process with d E (0. 1.5). Moreover, the consistency of the modified DW statistic as a unit root test against I ( d ) alternatives with d E ( 0 , l ) U ( 1 , 1.5) is proved in this paper. In addition to the theoretical analysis, Monte Carlo experiments show that the performance of the modified D W statistic reveals that it can be used as a unit root test against I ( d ) alternatives.     

Calendars and keys: The classification of “home” and “work”

This article presents a discussion of the relationship between classification systems and individuals' everyday activities. The concept of “boundary work” is defined as the practices that concretize and give meaning to mental frameworks by placing, maintaining, and challenging cultural categories. “Home” and “work” provide a case study for examining boundary work across a range of realm relationships, from those that are highly “integrating” to those that are highly “segmenting.” Boundary practices involving calendars and keys, clothes and appearances, eating and drinking, money, people and their representations (like photographs and gifts), talk styles and conversations, reading materials and habits, and work breaks (including lunches and vacations) are discussed. Mary Douglas's work on categorical purity helps illustrate the relationship between cognitive order and visible behavior seen in the boundary work of home and work. This article includes material that was published in a larger study,Home and Work: Negotiating Boundaries Through Everyday Life (1996 University of Chicago Press), after it was presented at the 1995 Eastern Sociological Society meetings in Philadelphia.