An Estimation Method of the Pair Potential Function for Gibbs Point Processes on Spheres

An estimation method for pairwise interaction potential of a stationary Gibbs point process is introduced by considering the case of observations located on a sphere. It is based both on Fourier decomposition of the potential and on minimum contrast estimation. It is defined when many independent realizations of the process are available. Consistency and asymptotic normality are proved for the resulting estimators. The method enables derivation of the choice of the potential function by embedded hypotheses testing. The method is applied to independent observations of root locations on internodes around stem of maize roots. The internodes are described as circles and we focus on the interaction function associated with the potential. Since a model with too many components seems to fail, we choose a sequential procedure based on embedded hypotheses testing to build a simpler model.     

Managing the flow of private information on children and parents in poverty situations: Creating a panoptic eye in interorganizational networks?

In this article, we discuss how the flow of private information about children and families in poverty situations is managed in interorganizational networks that aim to combat child poverty. Although practices for sharing information and documentation between child and family social work services are highly encouraged and recommended to create supportive features for parents and children, this development often results in undesirable forms of governmentality. Interorganizational networking also creates controlling side effects because the exchange of information in networks of child and family services may wield a holistic power over families. We theorize this issue by using the Foucauldian concepts of the panopticon and pastoral power, which allows us to grapple with the major tension between support and control in the information‐ and documentation‐sharing practices of social workers. A critical analysis of our empirical data reveals four central fields of tension in which social workers and their organizations must position themselves: (a) craving control and handling uncertainty, (b) using and misusing private information and trust, (c) constructing families as subjects and objects of intervention, and (d) including and excluding families.     

Social work and parent support in reaction to children's antisocial behaviour: constructions and effects

This article focuses on STOP4-7, an ecological early intervention programme for children with serious behavioural problems in Belgium, which includes social skills training for children, management training for parents and classroom management training for teachers. We argue how this type of social work benefits from empirical research on its effects on children and parents. Yet social work research that addresses these questions needs to extend its focus to overt and covert inclusion and exclusion mechanisms that operate through social work. Finally, we argue that, in the case of STOP4-7, social work is embedded in the process of social and political framing of the problems it is supposed to solve. By extending the focus of social work research to the very construction of social problems, we show how social workers may perform their agency as reflective practitioners, rather than being objects of interventions.     

What kind of Community measures for 1993?

During the ISSA General Assembly in Vienna in September 1989, a number of members from European Community countries expressed the wish that the ISSA should, as part of its programme, look into the social security consequences of the institution of the Single European Market after 1992. The ISSA General Secretariat consequently decided to carry out a survey of its member organizations in Community countries in order to draw up a directory of the studies carried out by these institutions, the aim being to identify problems related to the constitution of the so-called European social area, particularly the free movement of persons and goods, and review the measures that had been or were being implemented and the experience of institutions at the Community level. As a rule, in the countries in question, the heads of social security organizations are excluded from the bodies in which recommendations and rules are drawn up; on the other hand, the implementation and management of social security schemes do form part of their field of competence.
Some 40 member organizations replied to the survey questionnaire, and the ISSA General Secretariat requested Mr. Voirin, a specialist on European questions, to write the present article analysing the results.     

A note on the core and von Neumann-Morgenstern solutions of simple games

Following the results of Nakamura (1979) and Muto (1984), we derive, for a given proper voting game G, the upper bound on the size of the space of alternatives, which guarantees that the core constitutes a von Neumann-Morgenstern solution for any profile of voter's preferences. In particular, we show that if the space of alternatives consists of more than two elements, then, in general, the core is not a von Neumann-Morgenstern solution.We wish to thank Bezalel Peleg for pointing us out that one of the results in the previous version of this paper has already been proved by Muto (1984) and two anonymous referees for their useful remarks.     

The momentum of mortality change

Mortality change is not usually assigned much importance as a source of population growth when future population trends are discussed. Yet it can make a significant contribution to population momentum. In populations that have experienced mortality change, cohort survivorship will continue varying for some time even if period mortality rates become constant. This continuing change in cohort survivorship can create a significant degree of mortality-induced population change, a process we call the 'momentum of mortality change'. The momentum of mortality change can be estimated by taking the ratio of e0 (the period life expectancy at birth) to CAL (the cross-sectional average length of life) for a given year. In industrialized nations, the momentum of mortality change can attenuate the negative effect on population growth of declining fertility or sustained below-replacement fertility. In India, where population momentum has a value of 1.436, the momentum of mortality change is the greatest contributor to its value.     

Approval voting and positional voting methods: Inference,relationship, examples

Approval voting is the voting method recently adopted by the Society for Social Choice and Welfare. Positional voting methods include the famous plurality, antiplurality, and Borda methods. We extend the inference framework of Tsetlin and Regenwetter (2003) from majority rule to approval voting and all positional voting methods. We also establish a link between approval voting and positional voting methods whenever Falmagne et al.s (1996) size-independent model of approval voting holds: In all such cases, approval voting mimics some positional voting method. We illustrate our inference framework by analyzing approval voting and ranking data, with and without the assumption of the size-independent model. For many of the existing data, including the Society for Social Choice and Welfare election analyzed by Brams and Fishburn (2001) and Saari (2001), low turnout implies that inferences drawn from such elections carry low (statistical) confidence. Whenever solid inferences are possible, we find that, under certain statistical assumptions, approval voting tends to agree with positional voting methods, and with Borda, in particular.Michel Regenwetter thanks the National Science Foundation for funding this research through NSF grant SBR 97-30076. Both authors thank the Fuqua School of Business for financially supporting their collaboration. Most of this research was done while Regenwetter was a faculty member at Fuqua. We thank Prof. Steven Brams for his valuable comments as a discussant of a previous version of this paper, given at the 2002 Public Choice meeting, and Prof. Donald Saari for his helpful comments in conversations and on another draft. We also thank the editor in charge and a referee for their valuable comments. Tsetlin acknowledges the support of the Centre for Decision Making and Risk Analysis at INSEAD.     

General concepts of value restriction and preference majority

Regenwetter and Grofman [17] offer a probabilistic generalization of Sen's [25, 27] classic value restriction condition when individual preferences are linear orders. They provide necessary and sufficient conditions for transitive majority preferences on linear orders. They call these conditions net value restriction and net preference majority. We study parallel generalizations for general binary relations. In general, neither net value restriction nor net preference majority is necessary for transitive majority preferences. Net value restriction is sufficient for transitive strict majority preferences, but not sufficient for transitive weak majority preferences. Net majority is sufficient for transitive majorities only if the preference relation with a net majority is a weak order. An application of our results to four U.S. National Election Study data sets reveals, in each case, transitive majorities despite a violation of Sen's original value restriction condition. We thank the National Science Foundation for funding this collaborative research through NSF grants SBR 97-30076 to Regenwetter and SBR 97-30578 to Grofman and Marley. We are indebted to the Interuniversity Consortium for Political and Social Research (ICPSR) for access to the 1968, 1980, 1992 and 1996 U.S. National Election Study (NES) data. We thank Mark Berger for helping us with the necessary data extraction. We are grateful to the action editor and the referees for extensive and helpful comments. Most of this work was carried out while the first author was a faculty member at the Fuqua School of Business, Duke University, which has generously supported our collaboration. Marley was a fellow at the Hanse-Wissenschaftskolleg, Germany, during the paper's completion.     

Social security in central and eastern European countries: Continuity and change

Continued social protection in central and eastern Europe is vital in order to compensate for the loss of rights previously provided by the State, to ease the process of economic change and, not least, to maintain social cohesion without altogether subjecting populations to the vagaries of the market economy system. Long steeped in the tradition of social insurance, many of these countries had adapted their systems of protection to the Soviet model, while reflecting certain universal trends of social security policy, with an emphasis on family assistance. More recently, schemes have been complemented by unemployment benefits and by mechanisms to better take inflation into account, without prejudice to the necessary guarantee of a minimum level of assistance. They must still be adapted to facilitate occupational mobility, to promote employment, to involve the people covered by them in their management, and to deal with deteriorating health services, while taking account of problems stemming from resource limitation. Although reform must not obscure the need for continuity, uncertainty remains as to its outcome.