The wireless network jamming problem

In adversarial environments, disabling the communication capabilities of the enemy is a high priority. We introduce the problem of determining the optimal number and locations for a set of jamming devices in order to neutralize a wireless communication network. This problem is known as the wireless network jamming problem. We develop several mathematical programming formulations based on covering the communication nodes and limiting the connectivity index of the nodes. Two case studies are presented comparing the formulations with the addition of various percentile constraints. Finally, directions of further research are addressed.     

Gedanken zur Gestaltung einer professionellen Beratungsausbildung

Considerations on the design of a professional education of counselorsSome of the recently published articles about supervision-professionalizing are reflecting only sociological or psychological conceptions in order to describe and analyze professionality. In this article the authors discuss some of the mostly neglected points of view out of pedagogic and microsociologic professionalization-research (professional self, researching attitude). The existing requests of competence for supervisors are examined in order to test their teaching ability. Furthermore the content designs and didactic strategies for future counselor’s education are considered.     

Subhypergraph counts in extremal and random hypergraphs and the fractional <Emphasis Type="Italic">q</Emphasis>-independence

We study the extremal parameter N(n,m,H) which is the largest number of copies of a hypergraph H that can be formed of at most n vertices and m edges. Generalizing previous work of Alon (Isr. J. Math. 38:116–130, 1981), Friedgut and Kahn (Isr. J. Math. 105:251–256, 1998) and Janson, Oleszkiewicz and the third author (Isr. J. Math. 142:61–92, 2004), we obtain an asymptotic formula for N(n,m,H) which is strongly related to the solution α _q (H) of a linear programming problem, called here the fractional q-independence number of H. We observe that α _q (H) is a piecewise linear function of q and determine it explicitly for some ranges of q and some classes of H. As an application, we derive exponential bounds on the upper tail of the distribution of the number of copies of H in a random hypergraph.     

The heterogeneous impact of pension income on elderly living arrangements: evidence from China’s new rural pension scheme

This paper investigates the impact of pension income on living arrangements of the elderly. Taking advantage of a unique opportunity due to the recent establishment and expansion of the New Rural Pension Scheme in China, we explicitly address the endogeneity of pension status and pension income through a fixed-effect model with instrumental variable approach by exploiting exogenous time variation in the program implementation at county level. We find an overall positive effect of pension income on independent living as well as considerable heterogeneity. The positive income effects of the NRPS are concentrated among the elderly with adult children living nearby, of higher socio-economic status, and with better health at baseline; for other groups, the effects are insignificant. We also find that more generous programs exhibit larger effects. Our results highlight that living arrangement is multidimensional in rural China.     

How do labour laws affect unemployment and the labour share of national income? The experience of six OECD countries, 1970–2010

Using longitudinal data on labour law in France, Germany, Japan, Sweden, the United Kingdom and the United States over the period 1970–2010, the authors estimate the impact of labour regulation on unemployment and the labour share of national income. Their dynamic panel data analysis distinguishes between the short‐run and long‐run effects of regulatory change. They find that worker‐protective labour laws in general have no consistent relationship to unemployment but are positively correlated with labour's share of national income. Laws specifically relating to working time and employee representation are found to have beneficial effects on both efficiency and distribution thus proxied.     

Does It Matter How We Assess Standard of Living? Evidence from Indian Slums Comparing Monetary and Multidimensional Approaches

As part of Sustainable Development Goals, the United Nations have set targets of upgrading slums and reducing poverty in all its dimensions by 2030. Policies towards improving the living conditions of slum-dwellers require proper assessment of their standard of living as well as understanding the associated characteristics. In this paper, using slum-level primary household survey data from three largest Indian cities, we, first, assess the standard of living of slum dwellers using both monetary and non-monetary approaches and then explore how various household and spatial characteristics are consistently or differently associated with both forms of assessments. We use standard monetary indicators, but to assess non-monetary standard of living, use a counting approach framework and justify the selection of specific indicators in the context of slums. Our analysis yields some interesting observations as some characteristics are differently associated with monetary and non-monetary living standards, which should affect policy designs in slums.     

Estimating a sensitive proportion through randomized response procedures based on auxiliary information

Randomized response techniques are widely employed in surveys dealing with sensitive questions to ensure interviewee anonymity and reduce nonrespondents rates and biased responses. Since Warner’s (J Am Stat Assoc 60:63–69, 1965) pioneering work, many ingenious devices have been suggested to increase respondent’s privacy protection and to better estimate the proportion of people, π _A , bearing a sensitive attribute. In spite of the massive use of auxiliary information in the estimation of non-sensitive parameters, very few attempts have been made to improve randomization strategy performance when auxiliary variables are available. Moving from Zaizai’s (Model Assist Stat Appl 1:125–130, 2006) recent work, in this paper we provide a class of estimators for π _A , for a generic randomization scheme, when the mean of a supplementary non-sensitive variable is known. The minimum attainable variance bound of the class is obtained and the best estimator is also identified. We prove that the best estimator acts as a regression-type estimator which is at least as efficient as the corresponding estimator evaluated without allowing for the auxiliary variable. The general results are then applied to Warner and Simmons’ model.     

Droit du travail,chômage et part salariale: l'expérience de six pays de l'OCDE, 1970–2010

Utilisant des données sur le droit du travail dans six pays (Allemagne, Etats‐Unis, France, Japon, Royaume‐Uni et Suède) entre 1970 et 2010, les auteurs évaluent les effets de la réglementation du travail sur le chômage et la part du travail dans le revenu national. Leur méthode montre la différence entre les effets à court et à long terme des changements de réglementation: la législation protectrice des travailleurs n'est pas associée de façon systématique avec le chômage, mais est corrélée positivement avec la part du travail dans le revenu national. Les dispositions relatives au temps de travail et la représentation des salariés ont des effets bénéfiques tant sur l'efficacité que sur la répartition.