Domination and total domination in complementary prisms

Let G be a graph and be the complement of G. The complementary prism of G is the graph formed from the disjoint union of G and by adding the edges of a perfect matching between the corresponding vertices of G and . For example, if G is a 5-cycle, then is the Petersen graph. In this paper we consider domination and total domination numbers of complementary prisms. For any graph G, and , where γ(G) and γ _t (G) denote the domination and total domination numbers of G, respectively. Among other results, we characterize the graphs G attaining these lower bounds. Research supported in part by the South African National Research Foundation and the University of KwaZulu-Natal.     

Emerging coherence and relations to communication among executive function tasks in toddlers: Evidence from a Latin American sample

Recent work within early executive function (EF) seems to suggest that toddlers show distinct patterns of development, involving poorly correlated performance across EF tasks and significant improvements over relatively short periods of time. The present study sought to extend these findings by investigating evidence for these patterns in toddlers and the existence of more traditional patterns of EF (e.g., correlations between tasks, links to language) when using the same tasks in a novel Latin American sample. Eighty toddlers (18–24 months) and sixty young preschoolers (30–36) months completed a battery of EF tasks, early social communication, and receptive and expressive language measures. Results indicated that toddlers showed similar distinct patterns of development (i.e., few relations between tasks and links to responding to joint attention), but by early preschool a more cohesive EF and links to language were present. Further, work demonstrated significant age (older children outperformed younger children), gender (girls outperformed boys), and socioeconomic differences (satisfied basic needs outperformed unsatisfied basic needs, but only on the snack delay). This work provides evidence for patterns of emerging EF development within this novel cultural sample (and evidence for group differences) that may be supported by communicative and representational development.     

Factor copula models for right-censored clustered survival data

Lifetime Data Analysis - In this article we extend the factor copula model to deal with right-censored event time data grouped in clusters. The new methodology allows for clusters to have variable...     

Social development strategies of a non-governmental grassroots women's organisation in Nigeria

Social development initiatives of rural and poor urban women in Africa are efforts that redress the post-colonial economic development planning oversights of many African nations. Grass roots movements are responsive initiatives that have provided rural women with bottom-up management and planning opportunities focused on quality of life issues for themselves, their families, the community, and, ultimately, the nation. Since 1982, Country Women's Association of Nigeria (COWAN), a non-governmental organisation, has addressed the needs of rural and urban poor women through economic activities that have empowered them and increased their levels of self-sufficiency. With COWAN's emphasis on popular participation and indigenous leadership, macro-community development practices are employed, as is the recognition of individual and collective skills and talents. Social workers of today should be aware of commonalities that exists in the struggles of these and other Third World women, for their struggles are not unlike those of oppressed groups found in the USA and other developed countries.     

When Opportunity Knocks: Confronting Theory and Empirics About Dynamics of Gender Wage Inequality

Social Indicators Research - We present empirical evidence that large structural shocks are followed by changes in labor market inequality. Specifically, we study short-run fluctuations in adjusted...     

The impact of drug education and prevention programs. Disparity between impressionistic and empirical assessments

In the course of evaluating drug prevention programs for youth, we observed that although staff perceived the programs had quite favorably affected youths' attitudes and behavior, responses from these youths showed little significant impact on their use or attitudes related to drugs. This article explores several explanations for the disparity between staff impressions of the impact of these programs and results from attempts to measure impact objectivity. The analysis considers (a) clients' risk-level for drug use, (b) expectations as to how programs affect client behavior and attitudes, and (c) the sensitivity of empirical measures to ascertain changes reflecting impact of the program.     

The assembly of active participation by parents of children subject to a multi‐agency model of early intervention in child and family services

The Common Assessment Framework provides a model of early intervention, which is familiar in local authorities throughout England, and asserts a participatory framework of child and family engagement. This paper is based on a qualitative study of parents and children who were subject to a multi‐agency process of early intervention in children's social care in a local authority in the Midlands of England. I advance the concept of assemblage to consider the basis of an active service user participation as rather more a struggle to achieve than something that has been granted by practitioner agencies. Interview extracts are used to show the enrolment and assembly of participation as a process of service users developing their active human agency in a multi‐agency setting. The article explores the assembling of skills in administration and management of meetings and plans, accessing knowledge and expertise through service user networks, and challenging professional expertise and institutional space while developing personal qualities of confidence and voice as a means of marshalling an effective participation in a multi‐agency setting.     

AN OPEN‐ECONOMY MODEL WITH MONEY,ENDOGENOUS SEARCH,AND HETEROGENEOUS FIRMS

This paper describes a new monetary open‐economy model where firms have market power due to search frictions in the goods market, and endogenous search effort by consumers mitigates this market power. The optimal inflation rate generally depends positively on the cost of search effort, the cost of firm entry, and the cost of trade. Higher inflation always improves a country's terms‐of‐trade against its trading partners. I also characterize a general class of matching processes which offer a novel approach to modeling firm sales. (JEL D43, E40, F12)     

Bayesian modeling of temporal properties of infectious disease in a college student population

A Bayesian statistical model is developed for analysis of the time-evolving properties of infectious disease, with a particular focus on viruses. The model employs a latent semi-Markovian state process, and the state-transition statistics are driven by three terms: (i) a general time-evolving trend of the overall population, (ii) a semi-periodic term that accounts for effects caused by the days of the week, and (iii) a regression term that relates the probability of infection to covariates (here, specifically, to the Google Flu Trends data). Computations are performed using Markov Chain Monte Carlo sampling. Results are presented using a novel data set: daily self-reported symptom scores from hundreds of Duke University undergraduate students, collected over three academic years. The illnesses associated with these students are (imperfectly) labeled using real-time (RT) polymerase chain reaction (PCR) testing for several viruses, and gene-expression data were also analyzed. The statistical analysis is performed on the daily, self-reported symptom scores, and the RT PCR and gene-expression data are employed for analysis and interpretation of the model results.