Despite theoretical support for the role of the family in providing a foundation to protect youth against risks for aggression, there is little published literature examining a protective influence. This study examined family functioning and perceived parental messages about fighting and nonviolence as moderators of the relation between risk factors and adolescent aggression. The specific risk factors included affiliating with a delinquent group of peers, attending a school with norms that support aggression, and witnessing violence within the community. Secondary analyses were conducted on data collected from a high-risk sample of 537 adolescents in 2 cohorts from 18 schools. Adolescents completed measures of peer delinquent behavior and community violence exposure at the beginning and end of the sixth grade and at the end of the following two school years. An aggregated school-level measure of norms supporting aggression was constructed from a random sample of students in each cohort and school. Family variables included adolescent reports of parental messages supporting fighting and nonviolence, and family functioning classes created through a latent profile analysis of adolescent and parent reports of family cohesion, family problem-solving, parental involvement, and positive parenting. Aggression was assessed by a composite of ratings from parents, teachers, and adolescents. Longitudinal analyses indicated that delinquent peer associations and witnessing violence were each related to changes in aggression over time. School norms supporting aggression was not significantly related to aggression. Parental messages supporting nonviolence and not supporting fighting, and good family functioning at the start of the sixth grade were each related to lower subsequent levels of aggression. Few protective effects of family processes were found. High family functioning reduced the risk associated with delinquent peer associations. Lower levels of parental support for fighting buffered the risk associated with witnessing violence, but not at higher levels of witnessing violence. Thus, whereas a foundation of positive parental messages and good family functioning was associated with lower aggression overall, these family factors generally did not serve to protect adolescents that experienced higher levels of risk. These findings suggest a need for further study of protective factors for adolescents in the face of peer, school, and community risk.

We use a sample of US manufacturing firms from 1989 to 2018 in order to evaluate the effect of net working capital (NWC) on firm performance. We employ several econometric analyses to test our hypotheses and different specifications of our dependent and main variables of interest. Our results are robust and consistent with prior research on peer effects influencing corporate investment decisions. In addition, our results suggest that (i) the relation between excess working capital investment and company performance is non-linear (for firms with excessive working capital investment, the reduction in resources tied up in working capital in the previous year is positively associated with a better company performance over the subsequent year; however, for firms with low level of NWC, we cannot state that the opposite is true); (ii) we find significant peer effect that are positively associated with firms\' investment in working capital, and find that a one standard deviation increase in the average peer firm working capital investment leads to an 11% increase in firm i\'s investment, after controlling for firm-specific factors; and (iii) we estimate the impact of working capital investment on firm\'s performance using an instrumental variable framework that confirm that firms with a higher level of working capital are associated with worst level of firm\'s performance / Utilizamos uma amostra de empresas americanas de manufatura de 1989 a 2018 para avaliar o efeito do capital de giro líquido (NWC) sobre o desempenho da empresa. Empregamos várias análises econométricas para testar nossas hipóteses, assim como diferentes especificações de nossas variáveis dependentes e principal. Nossos resultados são robustos e consistentes com pesquisas anteriores sobre a influência dos pares sobre as decisões de investimento corporativo das empresas. Além disso, nossos resultados sugerem que: (i) a relação entre investimento em capital de giro e desempenho da empresa é não linear (para empresas com investimento excessivo em capital de giro, a redução de recursos atrelados ao capital de giro no ano anterior está positivamente associada a um melhor desempenho da empresa ao longo do ano subsequente; no entanto, para empresas com baixo nível de NWC, não podemos afirmar que o oposto é verdadeiro); (ii) encontramos um efeito significativo dos pares que está positivamente associado ao investimento das empresas em capital de giro, e descobrimos que um aumento de um desvio padrão no investimento em capital de giro médio dos pares leva a um aumento de 11% no investimento da empresa i, após controlar para fatores específicos da empresa; e (iii) estimamos o impacto do investimento em capital de giro no desempenho da empresa usando uma estrutura de regressão com variável instrumental que confirma que as empresas com nível excessivo de capital de giro estão associadas a um pior desempenho

O desenvolvimento da Internet motivou o surgimento de inúmeras aplicações que utilizam sua infra-estrutura. Dentre elas destacam-se as aplicações P2P para a transmissão de streamings de voz/vídeo. Essas aplicações exigem que determinados requisitos como largura de banda, latência, variação de atraso, escalabilidade, disponibilidade, entre outros, sejam satisfeitos para que possa haver qualidade no serviço provido (QoS Quality of Service). Satisfazer a todos esses requisitos torna-se um grande desafio quando é utilizada a infra-estrutura da Internet para transmissão. Deste modo, impulsionado pelo grande atrativo que existe no paradigma P2P, assim como todos os desafios por trás dessa abordagem, o objetivo principal deste trabalho é a proposta de um protocolo para a construção de overlays para a distribuição de streamings de vídeo em redes P2P. O protocolo proposto visa garantir que o overlay a ser empregado na distribuição de streamings seja construído, levando-se em consideração as características da rede física (nesse trabalho, a Internet) sob o mesmo. A idéia fundamental deste protocolo é organizar os pares de forma dinâmica, agrupando aqueles que estão mais próximos em termos de latência. O segundo objetivo a ser alcançado neste trabalho é a validação do protocolo por meio de experimentos (prova de conceito) realizados com o PlanetLab, de modo a validar os mecanismos propostos. / The Internet development has leveraged several kinds of application that depends on its infrastructure, such as P2P applications to voice/video streaming transmission. These applications have a plenty of requirements, such as bandwidth, latency, jitter, scalability, availability, and so on, that should be fulfilled in order to achieve the required level of Quality of Service (QoS). When it is used the Internet infrastructure to transmission, it is a great challenge fulfill all these requirements. In this manner, the main goal of this work is to propose a protocol to build an overlay to distribute video streaming in P2P networks, taking into account the network characteristics. The fundamental idea of this protocol is dynamically organize the peers, gathering these peers considering the latency between them. Another goal of this work is the protocol assessment by means of experiments (proof of concept) performed in PlanetLab, in order to verify the proposed mechanisms.

O desenvolvimento da Internet motivou o surgimento de inúmeras aplicações que utilizam sua infra-estrutura. Dentre elas destacam-se as aplicações P2P para a transmissão de streamings de voz/vídeo. Essas aplicações exigem que determinados requisitos como largura de banda, latência, variação de atraso, escalabilidade, disponibilidade, entre outros, sejam satisfeitos para que possa haver qualidade no serviço provido (QoS Quality of Service). Satisfazer a todos esses requisitos torna-se um grande desafio quando é utilizada a infra-estrutura da Internet para transmissão. Deste modo, impulsionado pelo grande atrativo que existe no paradigma P2P, assim como todos os desafios por trás dessa abordagem, o objetivo principal deste trabalho é a proposta de um protocolo para a construção de overlays para a distribuição de streamings de vídeo em redes P2P. O protocolo proposto visa garantir que o overlay a ser empregado na distribuição de streamings seja construído, levando-se em consideração as características da rede física (nesse trabalho, a Internet) sob o mesmo. A idéia fundamental deste protocolo é organizar os pares de forma dinâmica, agrupando aqueles que estão mais próximos em termos de latência. O segundo objetivo a ser alcançado neste trabalho é a validação do protocolo por meio de experimentos (prova de conceito) realizados com o PlanetLab, de modo a validar os mecanismos propostos. / The Internet development has leveraged several kinds of application that depends on its infrastructure, such as P2P applications to voice/video streaming transmission. These applications have a plenty of requirements, such as bandwidth, latency, jitter, scalability, availability, and so on, that should be fulfilled in order to achieve the required level of Quality of Service (QoS). When it is used the Internet infrastructure to transmission, it is a great challenge fulfill all these requirements. In this manner, the main goal of this work is to propose a protocol to build an overlay to distribute video streaming in P2P networks, taking into account the network characteristics. The fundamental idea of this protocol is dynamically organize the peers, gathering these peers considering the latency between them. Another goal of this work is the protocol assessment by means of experiments (proof of concept) performed in PlanetLab, in order to verify the proposed mechanisms.

Landmark-based architecture has been commonly adopted in the networking community as a mechanism to measure and characterize a host's location on the Internet. In most existing landmark based approaches, end hosts use the distance measurements to a common, fixed set of landmarks to derive an estimated location on the Internet. This paper investigates whether it is possible for participating peer nodes in an overlay network to collaboratively construct an accurate geometric model of its topology in a completely decentralized peer-to-peer fashion, without using a fixed set of landmarks. We call such a peer-to-peer approach in topology discovery and modeling using landmarks PALM (Peers As LandMarks). We evaluate the performance characteristics of such a decentralized coordinates-based approach under several factors, including dimensionality of the geometric space, peer distance distribution, and the number of peer-to-peer distance measurements used. We evaluate two PALM-based schemes: RAND-PALM and ISLAND. In RAND-PALM, a peer node randomly selects from existing peer nodes as its landmarks. In ISLAND (Intelligent Selection of Landmarks), each peer node selects its landmarks by exploiting the topological information derived based on existing peer nodes' coordinates values. / Singapore-MIT Alliance (SMA)

Numerous researchers have examined school and student variables that can prevent school failure, dropping out, and the development of delinquent behaviors. Such research suggests that students who establish a strong connection to school early in their academic career have higher academic achievement, better attendance, and more school participation (J. D. Finn, 1989, 1993; Finn & Rock, 1997; Sirin & Rogers-Sirin, 2005). However, there is little research that evaluates mechanisms that could be used to intervene when older students are on course for failure or delinquency. The current study, therefore, attempts to expand on the understanding of precipitating factors for school connection by investigating a possible link between school connection, extracurricular activity participation (EAP), and the relationships with teachers, parents, and peers promoted through activity participation. Latent variable structural equation modeling was used to investigate whether relationships with teachers, parents, and peers mediate the effects of EAP on school connection across time. Data from the base year (8th grade), first follow-up (10th grade), and second follow-up (12th grade) waves of the National Educational Longitudinal Study: 1988-2000 (NELS:88) were used. Three latent variable panel models were created and analyzed; one each for Relationships with Teachers, Relationships with Parents, and Relationships with Peers as the mediating variables. Results supported previous literature in that models reflecting a reciprocal relationship between EAP and school connection were found to have the best fit. Additionally, latent variable structural equation models were constructed to simultaneously compare the influence of EAP on the three types of relationships (i.e., with teachers, parents, and peers) and their subsequent influence on school connection. Finally, a latent variable structural equation model was constructed to explore possible differences in the type of activity in which a student participates on their relationships with others and school connection. / text

The thesis includes three empirical studies on Swedish children’s well-being. Central themes in these studies are how children’s social relations are influenced by and influence other dimensions of their well-being. The studies are framed in the introductory chapter, which includes an international comparison of children’s social relations. Study I analyses whether relations with parents and teachers are associated with the adolescent’s social background and whether the positive consequences of having strong relations are more important for disadvantaged adolescents. The results, based on nationally representa­tive survey data, confirm that strong social relations are conducive to adolescents’ school and psychological outcomes, and show that dis­advan­taged adolescents have weaker relations with parents and teachers. Furthermore, these results imply that relations with teachers are of particular importance for disadvantaged adolescents’ outcomes, while parental relations are equally important for both advantaged and dis­advantaged adolescents. Study II investigates the social side of consumption by studying the association between adolescents’ economic resources and their relations with peers. Analyses on nationally representative survey data; which include children’s own responses, as well as information from parents and register data, show that economic resources, in terms of both house­hold economy and adolescents’ own resources, are positively associated with peer relations. Study III analyses whether final grades in compulsory school are influenced by the sex composition in school classes. Analyses using register data show that boys’ grades are negatively affected by the share of girls in school classes in typical female school subjects. Girls’ grades are negatively affected by the share of boys with highly educated parents. The proposed explanation behind the results is that sex composition effects are due to negative social comparisons with the other sex. / At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Submitted.

A non-experimental survey design was used to study participant self-identified presence of secondary traumatic stress (STS) in Canadian school counsellors (N = 57) in relation to counsellors’ education and training, trauma-specific training, work experience, supervision, number of trauma clients and coping strategies. Counsellors were not necessarily protected from STS if they spent time using coping strategies, but were much less likely to be affected by STS if they engaged in supervision. Many school counsellors (59.6%) who participated in this research do engage in supervision, and those with trauma-specific training were less likely to have a peer-identified trauma disorder. Peer-identified trauma disorder played a large role in the results of this study. Participants identified as suffering from a trauma disorder were very likely to have a formal trauma diagnosis and were also likely to have higher traumatic stress scores. Implications for future research and education and training are discussed.

A non-experimental survey design was used to study participant self-identified presence of secondary traumatic stress (STS) in Canadian school counsellors (N = 57) in relation to counsellors’ education and training, trauma-specific training, work experience, supervision, number of trauma clients and coping strategies. Counsellors were not necessarily protected from STS if they spent time using coping strategies, but were much less likely to be affected by STS if they engaged in supervision. Many school counsellors (59.6%) who participated in this research do engage in supervision, and those with trauma-specific training were less likely to have a peer-identified trauma disorder. Peer-identified trauma disorder played a large role in the results of this study. Participants identified as suffering from a trauma disorder were very likely to have a formal trauma diagnosis and were also likely to have higher traumatic stress scores. Implications for future research and education and training are discussed.

The lobbying of Parliament and the Government in the United Kingdom by wealthy or influential groups and individuals raises concerns about corruption and political equality. Professional lobbying is available mainly to those with significant resources and is often the most effective means of influencing decision-makers. Unchecked, it corrodes public trust in core public institutions. This thesis argues that the problems attending the lobbying of Parliament and Government in the UK need to be identified and understood more clearly so that targeted regulatory solutions can be determined. Currently, lawmakers, organisations and academics have struggled to propose clear pathways for identifying the main issues and understanding them. This is due to a failure to agree on the nature and scope of the central problems associated with lobbying, the relationship between them, and how they are relevant to the model of democratic government in the UK. To overcome this, an analytical framework called ‘institutional diversion’ is developed, tested and evaluated. The framework is developed from institutional corruption literature in the United States and is divided into three parts. Part 1 provides elements which help to identify specific lobbying concerns and provide a rich account of the underlying issues. Part 2 articulates a test to determine whether the identified problem in Part 1 causes a diversion from the purpose of the relevant public institution. It is argued that the critical purpose of decision-makers in Parliament and the Government is to ‘act in the public interest’ and that a diversion from that purpose can be tested using the two criteria of ‘integrity’ and ‘objectivity’. Further, it is not sufficient for a framework to simply identify and help to understand the concerns with lobbying. The logical next step is to identify solutions, and that process must also be rationally guided. Therefore, guidelines are developed from an analysis of an interview with the Registrar of Consultant Lobbyists in the UK conducted specifically for this thesis. The guidelines are intended to help future reform analyses by highlighting the practical and political restrictions within which solutions must be developed otherwise they will be unlikely to succeed.