IMPROVING THE NUMERICAL TECHNIQUE FOR COMPUTING THE ACCUMULATED DISTRIBUTION OF A QUADRATIC FORM IN NORMAL VARIABLES

This paper is concerned with the technique of numerically evaluating the cumulative distribution function of a quadratic form in normal variables. The efficiency of two new truncation bounds and all existing truncation bounds are investigated. We also find that the suggestion in the literature for further splitting truncation errors might reduce computational efficiency, and the optimum splitting rate could be different in different situations. A practical solution is provided. The paper also discusses a modified secant algorithm for finding the critical value of the distribution at any given significance level.     

C++语言的高效性、共享性与重用性

分析了C 语言利用指针、引用、内联函数与友元提高程序运行效率的机制,利用静态数据成员及成员函数节省内存开销共享的机制,以及利用继承、模板与多态实现无限制重用已有程序代码的机制,指出C 语言更适合编写大型应用程序.     

两汉民俗区研究

民俗的重要特征是地域性,民俗区研究对研究区域历史文化有重要意义。自司马迁起,就开始将两汉民俗区划分为9个,后又有刘向、朱赣把全国划为13个民俗区,17个民俗亚区;今人周振鹤先生重新组合《汉书·地理志》的资料,把两汉民俗区划为三大民俗区域,16个民俗区,15个民俗亚区。以上划分法都有一定的缺憾,应划为四大民俗带:长城民俗带、黄河民俗带、长江民俗带、珠江民俗带。民俗区的形成有自然环境和政治环境的影响,相对南方而言,北方地区民俗受社会政治环境的影响更大一些。     

Arbeitsmarktforschung und Arbeitsmarktstatistik aus der Sicht der wirtschaftspolitischen Beratung: Erfahrungen und Perspektiven

Zusammenfassung: Dieser Beitrag beleuchtet aus der Sicht der wirtschaftspolitischen Beratung einige Anforderungen an die Arbeitsmarkt?konomik und Arbeitsmarktstatistik. Drei Bereiche werden angesprochen: die Arbeitslosenstatistik, die Tariflohnpolitik und die aktive Arbeitsmarktpolitik. Dabei werden zun?chst die Bemühungen hinsichtlich einer realistischeren Erfassung der Unterbesch?ftigung gewürdigt, zugleich aber Hinweise auf Verbesserungsm?glichkeiten gegeben. Anforderungen an die amtliche Statistik ergeben sich des Weiteren hinsichtlich der Tarifentgelte. In diesem Zusammenhang wird die Umsetzung der Erkenntnisse der Arbeitsmarkt?konomik in eine lohnpolitische Orientierungshilfe skizziert. Schlie?lich erfolgt eine kritische Einsch?tzung des Erfolgs der aktiven Arbeitsmarktpolitik, wobei eine zunehmende Willigkeit zur Bereitstellung der für die Evaluation erforderlichen Daten konstatiert werden kann.

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Summary: This paper deals with three demands on labor economics and labor statistics put forward from the point of view of an advisor to economic policy. Despite several improvements of unemployment statistics, a lot of work remains to be done. With respect to wage policy attempts by the German Council of Economic Experts are discussed how to formulate a guidance for wage policy both on scientific grounds and understandable by the public. Finally, a critical assessment of active labor market policies is presented together with a plea for adequate individual data in order to carry out a sound evaluation of these policies.

* Vortrag für die „Statistische Woche“, die Jahrestagung der Deutschen Statistischen Gesellschaft am 20. September 2004 in Frankfurt/Main. Der Vortragsstil wurde beibehalten. Die hier vorgetragenen Auffassungen liegen allein in der Verantwortung des Autors und stellen nicht notwendigerweise die Auffassungen anderer Institutionen dar. Ich danke Bernd Fitzenberger (Universit?t Frankfurt/Main und ZEW), Joachim M?ller (Universit?t Regensburg), Bernhard Boockmann und Tobias Hagen (ZEW), Irmtraud Beuerlein und Dirk Heinlein (Statistisches Bundesamt) für hilfreiche Kommentare und Anregungen. Verbleibende M?ngel gehen—leider—zu meinen Lasten.     

EDF tests of goodness of fit for transform-both-sides models

Very often in regression analysis, a particular functional form connecting known covariates and unknown parameters is either suggested by previous work or demanded by theoretical considerations so that the deterministic part of the responses has a known form. However, the underlying error structure is often less well understood. In this case, the transform-both-sides (TBS) models are appropriate. In this paper we generalize the usual TBS models and develop tests to assess goodness of fit when fitting TBS or GTBS models. Parameter estimation is discussed, and tests based on the Cramér-von Mises statistic and the Anderson-Darling statistic are presented with a table suitable for finite-sample applications.     

Macroeconomic conditions, institutional factors and demographic structure: What causes welfare caseloads?

Some of the possible determinants of changes observed in welfare caseloads are analysed in this study. The paper attempts to explain variations in welfare caseloads on the basis of four different factors: macroeconomic conditions, interactions with other income maintenance programmes, changes in the programme's parameters and changes in the demographic structure. Different models are tested by applying time series techniques. The data employed are of an administrative nature and cover the whole period that the Madrid programme has been in operation. The results show that the effects of both unemployment and institutional variables are strong and significant. Macroeconomic effects on caseloads could be offset or reinforced by changes in unemployment protection and reforms of the programme's parameters. The significant effects found for the share of lone-parent applicants also show that demographic shifts could shape the trends of welfare rolls regardless of the changes in unemployment or the implementation of institutional reforms. The authors would like to thank Juan Gabriel Rodríguez, Minoru Kunizaki, Miguel Angel Malo and three anonymous referees for their comments and suggestions. Financial and technical support from the Spanish Institute for Fiscal Studies, the Inter-ministerial Commission on Science and Technology (SEC 2001-0746) and the Social Services Department of the Madrid Government is also gratefully acknowledged. Responsible editor: Christian Dustmann.     

C—代数的特征矩阵的性质

本主讨论了C-代数的特征矩阵的性质,并获得了求特征矩阵的逆的一个方法。     

以C语言为主线整合数字化技术课程群

文章阐述了以C语言程序设计方法为主线,将《C语言程序设计》、《EDA技术及应用》(EDA—E lec-tron ic Design Autom ation)、《虚拟仪器》(VI—V irtual Instrum entations)、《DSP技术与应用》(DSP—D igital S ig-nal Processor)等四门具有典型数字化特征的课程进行有机融合,以形成数字化专业技术课程群的思路、方法和措施。论述了课程的地位和可融合性、课程相关技术的先进性、整合与建设的必要性和可行性,提出了建设校级一类课程和省级优质课程的目标和相关措施。     

论《海商法》中实际承运人的相关法律问题

实际承运人是海上货物运输实践中的重要当事方 ,由于《海商法》对实际承运人的法律界定很不明晰 ,造成了实践中的混乱。本文以实际承运人的概念阐述为基础 ,对多种情况下实际承运人识别问题进行了划分 ,并探讨了实际承运人责任认定的相关法律问题。     

克孜尔石窟年代研究和碳十四测定数据的应用

本文介绍了克孜尔石窟年代分期的几种意见,碳十四测定为克孜尔石窟年代分期研究开辟了新的途径。科学技术的发展、科学测定方法的进步和完善,是解决石窟分期问题的希望所在。