Compact labelings for efficient first-order model-checking

We consider graph properties that can be checked from labels, i.e., bit sequences, of logarithmic length attached to vertices. We prove that there exists such a labeling for checking a first-order formula with free set variables in the graphs of every class that is nicely locally clique-width-decomposable. This notion generalizes that of a nicely locally tree-decomposable class. The graphs of such classes can be covered by graphs of bounded clique-width with limited overlaps. We also consider such labelings for bounded first-order formulas on graph classes of bounded expansion. Some of these results are extended to counting queries.     

National Defense,Environmental Regulation,and Overhead Democracy: A View from the “Greening” of the U.S. Military

This study examines the patterns of politics accompanying efforts to hold the United States military accountable to U.S. environmental and natural resources (ENR) laws in the post-Cold War era. This analysis (1) uses three cases to describe what happened, and why, (2) to test several propositions related to military accountability to ENR laws in the post-Cold War era; (3) to offer a typology of tactics used that may help inform future research on intragovernmental regulation more generally; and (4) argues that public agencies have a responsibility to comply with the regulatory processes that hold them accountable to U.S. ENR laws.     

Cross-country determinants of life satisfaction: exploring different determinants across groups in society

This paper explores a wide range of cross-country determinants of life satisfaction exploiting a database of 90,000 observations in 70 countries. We distinguish four groups of aggregate variables as potential determinants of satisfaction: political, economic, institutional, and human development and culture. We use ordered probit to investigate the importance of these variables on individual life satisfaction and test the robustness of our results with Extreme Bounds Analysis. The results show that only a small number of factors, such as openness, business climate, postcommunism, the number of chambers in parliament, Christian majority, and infant mortality, robustly influence life satisfaction across countries while the importance of many variables suggested in the previous literature is not confirmed. This remains largely true when the analysis splits national populations according to gender, income, and political orientation also. We thank Stephen Lea, participants at the 30th IAREP conference in Prague and the referees of this journal for comments on earlier versions. Gilles Winkler provided excellent research assistance.     

Assessing the Moderating Effects of Depressive Symptoms on Antisocial Behavior among Urban Youth in Public Housing

This study assesses whether the influences of attitude towards deviance, exposure to delinquent peers and parental supervision and encouragement on antisocial behavior are moderated by depressive symptoms. Two hundred and thirty eight African American adolescents ages 13–19 from three public housing developments participated in this study. Results indicate that approximately half of the youth did not engage in antisocial behaviors in the last year. Gender, depression, attitudes and peers were significant correlates of antisocial behavior. Parental supervision and encouragement, and age were not related to antisocial behavior. Interaction effects suggest that the relative influences of attitudes towards deviance and delinquent peers on antisocial behaviors depend upon gender and level of depression symptoms. Implications for social work practice and future research are discussed.     

Beneficial safety decreases

We construct a model of rational choice under risk with biased risk judgement. On its basis, we argue that sometimes, a regulator aiming at maximising social welfare should affect the environment in such a way that it becomes ‘less safe’ in common perception. More specifically, we introduce a bias into each agent’s choice of optimal risk levels: consequently, in certain environments, agents choose a behaviour that realises higher risks than intended. Individuals incur a welfare loss through this bias. We show that by deteriorating the environment, the regulator can motivate individuals to choose behaviour that is less biased, and hence realises risk levels closer to what individuals intended. We formally investigate the conditions under which such a Beneficial Safety Decrease—i.e. a deteriorating intervention that has a positive welfare effect—exists. Finally, we discuss three applications of our model.     

Geometric rounding: a dependent randomized rounding scheme

We develop a new dependent randomized rounding method for approximation of a number of optimization problems with integral assignment constraints. The core of the method is a simple, intuitive, and computationally efficient geometric rounding that simultaneously rounds multiple points in a multi-dimensional simplex to its vertices. Using this method we obtain in a systematic way known as well as new results for the hub location, metric labeling, winner determination and consistent labeling problems. A comprehensive comparison to the dependent randomized rounding method developed by Kleinberg and Tardos (J. ACM 49(5):616–639, 2002) and its variants is also conducted. Overall, our geometric rounding provides a simple and effective alternative for rounding various integer optimization problems.     

The role,power and influence of company chairs

This paper develops an analytical framework to depict the heterogeneity that characterises the role of board chair and demonstrate the potential variability in how chairs operate boards and exercise power and influence on strategy, control and resource related tasks at board level. Theories of power and influence, as applied to top management teams and boards of directors, are explicated within the context of contemporary governance practices that are establishing the role of the board chair as distinct to that of the chief executive officer. Specifically, the paper maps sources of power and varying contemporary chair practices, including chair nomenclature (i.e. executive vs. non-executive chairs), chair origin (insider vs. outsider) and chair time (full-time vs. part-time). A number of theoretical chair-power models emerge from this analysis and are subject to empirical analysis using data collected from 160 chairs of 500 FTSE-listed companies. Theoretically and empirically, the paper complements structural approaches to studying boards with attention to behaviour on boards. By linking board structure, board process and the exercise of influence, the study reveals both differences amongst chairs in how they run the board, but also that chairs’ differ in the influence they exert on board-related tasks. Full-time executive chairs exert their greatest influence in strategy and resource dependence tasks whereas part-time, non-executive chairs seem to exert more influence over monitoring and control tasks.     

Demand for health risk reductions: A cross-national comparison between the U.S. and Canada

Using a large stated preference survey conducted across the U.S. and Canada, we assess differences in individual willingness to pay (WTP) for health risk reductions between the two countries. Our utility-theoretic choice model allows for systematically varying marginal utilities for avoided future time in different adverse health states (illness-years, recovered/remission years, and lost life-years). We find significant differences between Canadian and U.S. preferences. WTP also differs systematically with age, gender, education, and marital status, as well as a number of attitudinal and subjective health-perception variables. Age profiles for WTP are markedly different across the two countries. Canadians tend to display flatter age profiles, with peak WTP realized at older ages.