It Takes Two to Fight in School,Too: A Social Relations Model of the Psychometric Properties and Relative Variance of Dyadic Aggression and Victimization in Middle School

Aggressive behavior has been well studied in terms of interindividual differences among aggressors and victims, but has been understudied, especially within naturalistic contexts, in terms of aggressor–victim relationships. The social relations model (SRM) is a powerful conceptual and analytic tool for studying dyadic phenomena, and we describe the use of multivariate SRM to study aggression. Boys and girls (N = 210) in middle schools (sixth and seventh grades) completed a newly created dyadic aggression and victimization inventory (DAVI). Results support the reliability and validity of the DAVI in assessing inter‐individual and inter‐dyadic differences in aggression and victimization. Occurrences of aggression were accounted for primarily by inter‐dyadic variability, indicating the importance of considering aggressor–victim relationships. We discuss the implications of this relationship focus for future research and intervention efforts.     

The Role of Criminal Social Identity in the Relationship between Criminal Friends and Criminal Thinking Style within a Sample of Recidivistic Prisoners

Previous research suggests a direct relationship between criminal friends and criminal thinking style; however, social identity theory proposes that identity mediates the impact of social group members on development of thinking styles. This research project is the first attempt to empirically test the mediating role of criminal social identity in the development of criminal thinking styles within a recidivistic prison sample (N = 312). The structural equation model of criminal thinking style presented and tested in this study supports the central predictions of social identity theory, with findings demonstrating an indirect effect of antisocial friend associations on criminal thinking through in-group affect and in-group ties with criminal in-group members that reflect two of three dimensions of the measure of criminal social identity applied in the current study. Further implications in relation to theory and previous studies are discussed.     

Neighborhood Conditions,Parenting, and Adolescent Functioning

ABSTRACT

This study examined youth self-reported data from a 4-year longitudinal study of 5th and 8th grade youth and their parents. Relationships between neighborhood conditions, parenting, and youth antisocial behavior were tested using structural equation modeling. The findings of this study appear to suggest there are two social forces that affect youth antisocial behavior: parenting and neighborhood conditions. Higher levels of parental acceptance and monitoring are directly and significantly associated with lower levels of youth antisocial behavior, as are higher levels of community social integration and lower levels of youth loneliness. Overall, it was found that some measures of neighborhood conditions and some measures of parenting were relatively equally predictive of youth antisocial behavior. Other measures of neighborhood conditions were predictive of parenting, but not strongly enough to also impact adolescent functioning.     

Longitudinal predictors of reading achievement among at-risk children

Early exposure to multiple risk factors is related to an elevated risk for academic difficulty. Thus, it is important to promote academic resilience as early as possible and to identify factors that support resilience. Given the positive relation between early literacy skills and later academic outcomes, examining resilience in reading is important. This study examined, first, whether the reading gap widens or narrows for below-average and above-average, at-risk children during the first four years of school; and, second, what protective factors predict reading achievement over time from kindergarten through the end of third grade. Results indicated that as a group, low-achieving children made smaller gains in reading than high-achieving children over the first four years of school. In addition, participation in center-based prekindergarten care, plus more access to books in the home, better interpersonal skills, and fewer poor physical conditions immediately surrounding elementary schools served as protective factors for at-risk children's early literacy development.     

ROC Curves in Non‐Parametric Location‐Scale Regression Models

Abstract. The receiver operating characteristic (ROC) curve is a tool of extensive use to analyse the discrimination capability of a diagnostic variable in medical studies. In certain situations, the presence of a covariate related to the diagnostic variable can increase the discriminating power of the ROC curve. In this article, we model the effect of the covariate over the diagnostic variable by means of non‐parametric location‐scale regression models. We propose a new non‐parametric estimator of the conditional ROC curve and study its asymptotic properties. We also present some simulations and an illustration to a data set concerning diagnosis of diabetes.     

Adolescent Sibling Relationship Quality and Adjustment: Sibling Trustworthiness and Modeling,as Factors Directly and Indirectly Influencing These Associations

The main goal of this study was to examine the direct and moderating effects of trustworthiness and modeling on adolescent siblings' adjustment. Data were collected from 438 families including a mother, a younger sibling in fifth, sixth, or seventh grade (M = 11.6 years), and an older sibling (M = 14.3 years). Respondents completed Web‐based surveys describing sibling conflict and warmth. Siblings reported on trustworthiness and modeling, and mothers described adjustment. Sibling conflict was directly associated with internalizing and externalizing behaviors for both siblings. The older siblings' reports of trustworthiness were directly associated with the outcome measures. The younger siblings' reports of trustworthiness were less directly associated, but a possible salutary effect was most evident under the highest levels of sibling conflict or warmth. Higher sibling modeling was a risk factor for adjustment problems in relations characterized by high conflict. Results support exploring trustworthiness as a key dimension of sibling relations.     

A Bayesian model for estimating the malaria transition probabilities considering individuals lost to follow-up

It is known that patients may cease participating in a longitudinal study and become lost to follow-up. The objective of this article is to present a Bayesian model to estimate the malaria transition probabilities considering individuals lost to follow-up. We consider a homogeneous population, and it is assumed that the considered period of time is small enough to avoid two or more transitions from one state of health to another. The proposed model is based on a Gibbs sampling algorithm that uses information of lost to follow-up at the end of the longitudinal study. To simulate the unknown number of individuals with positive and negative states of malaria at the end of the study and lost to follow-up, two latent variables were introduced in the model. We used a real data set and a simulated data to illustrate the application of the methodology. The proposed model showed a good fit to these data sets, and the algorithm did not show problems of convergence or lack of identifiability. We conclude that the proposed model is a good alternative to estimate probabilities of transitions from one state of health to the other in studies with low adherence to follow-up.     

基于产业集群的企业重点投资地区决策的仿真

用多Agent仿真技术,研究了基于产业集群的台资IT企业在大陆重点投资地区的决策问题。提出了针对这一问题的、将集群竞争力评价的GEM模型、多Agent仿真技术及演化博弈相结合的思路与方法。仿真模型对集群的研究方法以及多Agent的应用领域有拓展意义,而仿真发现与结论可为政府制定有关政策提供参考。     

Effects of the Mechanism of Receptor-Mediated Gene Expression on the Shape of the Dose-Response Curve

A mathematical model of receptor-mediated gene expression that includes receptor binding of natural and xenobiotic ligands, protein synthesis and degradation, and metabolism of the xenobiotic ligand was created to identify the determinants of the shape of the dose-response profile. Values of the model's parameters were varied to reflect alternative mechanisms of expression of the protein. These assumptions had dramatic effects on the computed response to a bolus dose of the xenobiotic ligand. If all processes in the model exhibit hyperbolic kinetics, the dose-response curves can appear sigmoidal but actually be linear with a positive slope at low doses. The slope of the curve only approached zero at low dose, indicative of a threshold for response, if binding of the xenobiotic ligand to the receptor exhibited positive cooperativity (ligand binding at one site increases the affinity for ligand at another binding site on the receptor). Positive cooperativity in the rate-limiting step of protein synthesis produced dose-response curves which were "U-shaped" at low doses, also indicative of a threshold. Positive cooperativity in the metabolism of the xenobiotic ligand produced dose-response curves that increased more rapidly than linearly with increasing dose. The model illustrates the fact that response cannot be predicted from qualitative mechanistic arguments alone; any assessment of risk to health from xenobiotic chemicals must be based on a detailed quantitative examination of the kinetic behavior of each chemical species individually.