The uncovered set in spatial voting games

In a majority rule voting game, the uncovered set is the set of alternatives each of which can defeat every other alternative in the space either directly or indirectly at one remove. Research has suggested that outcomes under most reasonable agenda processes (both sincere and sophisticated) will be confined to the uncovered set. Most research on the uncovered set has been done in the context of voting games with a finite number of alternatives and relatively little is known about the properties of the uncovered set in spatial voting games.We examine the geometry of the uncovered set in spatial voting games and the geometry of two important subsets of the uncovered set, the Banks set and the Schattschneider set. In particular, we find both general upper and lower limits on the size of the uncovered set, and we give the exact bounds of the uncovered set for situations with three voters. For situations with three voters, we show that the Banks set is identical to the uncovered set.     

Partnerships, Power and the "New" Politics of Community Participation in British Health Care

Multi–sectoral approaches to health improvement in its broadest sense have entailed an emphasis by the British government upon partnership working in and around community involvement in planning processes. New service planning and delivery organizations in the health service—primary care groups and primary care trusts—thus have to ensure that public and patient involvement strategies reflect a coordinated, if not integrated, multi–sectoral approach to such involvement. But how are these enforced partnership arrangements shaping the approach taken by primary care groups and trusts to the issue of public and patient involvement? More particularly, is the traditional dominance of health service managers and the medical profession in decision–making processes under challenge? This article draws on a study of primary care groups and trusts in three districts in order to gauge perceptions and calculations with regard to partnerships for involvement. Results appear to suggest that health service managers and practitioners continue to exercise considerable influence in comparison to that of patients and citizens. But, if the findings are viewed in the broader contexts of government managerialist strategies of surveillance and accountability and the growth of service–user and advocacy organizations, partnerships may offer significant scope for “lay” challenges to managerial and medical power.     

Sterilization: Whose Right to Choose?

As there is presently no safe, freely available and fully effective mode of contraception, voluntary sterilization remains a matter of importance in this sphere. The legal right to such a choice has slowly evolved and it now seems clear that there is no legal barrier to such a choice by a competent adult. Yet, at a practical level, it seems that hospitals and medical practitioners will not readily accede to a request by an individual for such an operation and usually insist on the consent of the spouse if the person is married. The disparity between the law and existing practice is examined. It is argued that an adult individual should basically have a right to determine what shall be done with his own body, and that the onus is heavily on those who exceptionally seek to justify intervention.     

The Role of Social Distrust in Risk-Benefit Analysis: A Study of the Siting of a Hazardous Waste Disposal Facility

Distrust of social institutions is becoming an important component of risk communication and policy analysis. To assess the impact of social distrust on decision making, we examine the role of distrust of information sources on the willingness to accept a hazardous waste disposal facility in one's neighborhood. Using a prospective-reference utility model, distrust of information sources is analyzed a possible influence on individual choice in a risk-benefit tradeoff. Using contingent valuation survey data on the siting of a hazardous waste disposal facility, we find that respondents are particularly distrustful of both governmental officials and waste disposal businesses. We find that social distrust increases the perceived risk of a facility and influences the likelihood of accepting a referendum to site a hazardous waste disposal facility. The level of compensation offered in the contingent valuation scenario also is found to influence a respondent's risk perception.     

Performing armchair roundoff analyses of statistical algorithms

Numerical stability is but one of many desirable properties which should be considered when designing statistical software. However, rigorous roundoff analysis is rarely done because it seems not worth the price; the influence of rounding error is usually of secondary importance, and the analysis is thought to be beyond the reach of all but a few specialists. This note discusses the role of roundoff analysis in the design of a statistical program and shows that new techniques sometimes make assessment of the effect of rounding errors no more difficult than the verification of other program properties.     

A Characterization of the Normal Family of Distributions Based on the Bias of the Maximum Likelihood Estimator

This paper characterizes the family of Normal distributions within the class of exponential families of distributions, via the structure of the bias of the maximum likelihood estimator Θ _n of the canonical parameter Θ . More specifically, when E _θ ( Θ n ) – Θ = (1/ n ) Q ( Θ ) + o (1/ n ), the equality Q ( Θ ) = 0 proves to be a property of the Normal distribution only. The same conclusion is obtained for the one-dimensional case bt assuming that Q ( Θ ) is a polynomial of Θ .