Verification of the ages of supercentenarians in the United States: Results of a matching study

Unprecedented declines in mortality among the very old have led to the emergence of "true" supercentenarians (persons aged 110 and over). The ages of these individuals have been well-documented in European countries with a history of birth registration, but have not been systematically studied in the United States, which lacks similar documentation and where the inaccuracy of age reporting has been an issue. To verify age, we linked records from the Social Security Administration for close to 700 individuals who died from 1980 to 1999 purportedly at ages 110 and older to records of the U.S. censuses of 1880 and 1900, conducted when these individuals were children. This group was a residual group from an earlier file that was reduced by the SSA after data checks that eliminated incorrect records. The results of the matched records for the residual file indicate that over 90% of the whites were accurately reported as supercentenarians, but only half of the blacks appeared to have attained age 110. The verification of age shows that the United States has more "true" supercentenarians than do other nations.     

Parental leave: The impact of recent legislation on parents’ leave taking

We use data from the Survey of Income and Program Participation to examine the impact of leave entitlements on unpaid leave usage by men and women after the birth of a child from 1991 to 1999. The results indicate that legislation providing the right to unpaid leave has not affected men's leave usage. The results for women are mixed: in some specifications, leave entitlements are associated with increased leave taking or longer leaves, but the results depend on how we define leave coverage. Our results point to the limited impact of unpaid leave policies and the potential importance of paid-leave policies.     

Assimilation of immigrants: Implications for human capital accumulation of the second generation

Immigrants assimilate in various dimensions at different rates. Moreover, in each of these dimensions they assimilate at rates that may differ from those of their children. The purpose of this paper is to examine how the pace of assimilation of immigrants in various dimensions affects the rate of human capital accumulation of immigrant children. It is argued that rapid assimilation in certain dimensions serves to increase the rate of human capital accumulation of the second generation, while in other dimensions it may have the opposite effect.I thank Christoph Schmidt, Peter Schaeffer, and two anonymous referees for helpful comments. Responsible editor: Christoph M. Schmidt.     

双语教学与“文化侵入”

文章从语言的功能、语言与文化的关系、双语教学的必要性和双语教学中的语言关系等方面,阐述了"双语教学"并非"文化入侵",而是时代发展的必然,是社会进步的表现.     

显微成像数字化及教学应用

文章利用现有设备状况,采取"光学显微镜+摄像机或普通数码照相机+图像采集卡"的方案,进行了显微图像数字化系统的研究。该方案充分挖掘现有设备的潜力,具有很强的实用性和可观的经济价值。     

试论"与时俱进"的理论品质

"与时俱进"丰富和发展了马克思主义的哲学范畴及其整个理论体系,它概括了当今时代的本质、内容和基本特征,体现了时代精神,具有鲜明的时代性."与时俱进"要求以人作为主体的自觉能动的实践活动为中心,运用开拓创新的思维方式、研究方法、实践手段去研究与掌握人与世界的总体性关系.因此,"与时俱进"具有时代性、主体性和创新性三个方面的理论品质.     

Impartiality and interpersonal comparisons of variations in well-being

The moral imperative requiring equal treatment of equal claims, or impartiality, is defined in the frameworks of Harsanyi's aggregation and impartial observer theorems as an axiomatic restriction of the underlying moral value judgments. The implications of impartiality for the functional form of the corresponding social welfare functions are derived and are shown to entail interpersonal comparison of variations in well-being. The argument is illustrated with examples.This paper was written while I visited CORE at the Universite Catholique de Louvain and Universite Sorbonne-Pantheon (Paris I). I am grateful to both institutions for their hospitality. I am also grateful to Omer Alper, Philippe Mongin, Zvi Safra, and Uzi Segal for their useful comments.     

Farsighted stability in hedonic games

We investigate how rational individuals partition themselves into different coalitions in hedonic games (see Banerjee et al. 2001 and Bogomolnaia and Jackson 2002), where individuals' preferences depend solely on the composition of the coalition they belong to. Given that the four solution concepts studied in the literature (core, Nash stability, individual stability and contractual individual stability) may exhibit myopia on the part of the players, we amend these notions by endowing players with foresight in that they look many steps ahead and consider only credible outcomes. We study the properties of the farsighted stability solutions; in particular, we show that when preferences are strict, coalition structures in the core are farsighted stable and a similar result also holds for Nash stability but not for individual stability and contractual individual stability. We thank Birgit Grodal, Hideo Konishi, an associate editor and two referees for their helpful comments and suggestions. Thanks also go to the audiences at University of Copenhagen, CSAET, 2001, Workshop on Coalitions and Networks at Warwick, 2001, and International Game Theory Conference at Stony Brook, 2001.     

The impossibility of a Paretian egalitarian

In a one-good world, there is a nice correspondence between the Pigou-Dalton principle of transfer and social welfare dominance. In this paper we study the case of multiple goods (without using prices as a means to come back to one dimension), and show that many results of the one-dimensional setting carry over to the multidimensional case when individuals are assumed to have identical preferences. But the nice correspondence breaks down as soon as individual preferences display minimal differences, and multidimensional versions of the transfer principle clash with the Pareto principle. This analysis reveals an interesting connection with the theory of fair allocation, since multidimensional transfer principles are closely related to the no-domination criterion, a weak version of the no-envy criterion.For helpful comments, we thank J. L. Castillo, M. Le Breton, Y. Sprumont, K. Suzumura and participants at a workshop in Osnabrück, a LivinTax conference in Bordeaux and a seminar in Hitotsubashi University, as well as two referees. Financial support from TMR project Living Standards, Inequality and Taxation Contract no ERBFMXCT 980248 of the European Commission is gratefully acknowledged. We thank Michel Le Breton for giving us the permission to state a result contained in his unpublished Ph D thesis.     

Trust and functional foods. New products,old issues

Trust in the "agro-food" sector has been declining in recent years reflecting a general decline of trust in traditional decision making processes. The introduction of new technologies in the production of foods re-introduces the problem of trust and highlights the parameters affecting its structure and direction. This paper discusses the issue of trust in relation to the introduction of functional foods into the market. Trust is assessed as both a philosophical and a psychological construct with particular emphasis on its communication aspects. The paper ends with specific recommendations for action in the agro-food sector. This paper partly reflects work done with Professor Cees Midden, Technical University of Eindhoven, as part of an expert technology assessment project for the Europaeische Akademie Bad Neuenahr Ahrweiler GmbH.