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511.
AStA Advances in Statistical Analysis - If one is to judge by counts of citations of the fundamental paper (Dempster in JRSSB 39: 1–38, 1977), EM algorithms are a runaway success. But it is... 相似文献
512.
Jennifer K. MacCormack Vanessa L. Castro Amy G. Halberstadt Megan L. Rogers 《Social Development》2020,29(2):578-599
Interoception, often defined as the perception of internal physiological changes, is implicated in many adult social affective processes, but its effects remain understudied in the context of parental socialization of children's emotions. We hypothesized that what parents know about the interoceptive concomitants of emotions, or interoceptive knowledge (e.g., “my heart races when excited”), may be especially relevant in emotion socialization and in supporting children's working models of emotions and the social world. We developed a measure of mothers' interoceptive knowledge about their own emotions and examined its relation to children's social affective outcomes relative to other socialization factors, including self‐reported parental behaviors, emotion beliefs, and knowledge of emotion‐relevant situations and non‐verbal expressions. To assess these, mothers (N = 201) completed structured interviews and questionnaires. A few months later, third‐grade teachers rated children's social skills and emotion regulation observed in the classroom. Results indicated that mothers' interoceptive knowledge about their own emotions was associated with children's social affective skills (emotion regulation, social initiative, cooperation, self‐control), even after controlling for child gender and ethnicity, family income, maternal stress, and the above maternal socialization factors. Overall, findings suggest that mothers' interoceptive knowledge may provide an additional, unique pathway by which children acquire social affective competence. 相似文献
513.
AbstractGrubbs and Weaver (1947) suggest a minimum-variance unbiased estimator for the population standard deviation of a normal random variable, where a random sample is drawn and a weighted sum of the ranges of subsamples is calculated. The optimal choice involves using as many subsamples of size eight as possible. They verified their results numerically for samples of size up to 100, and conjectured that their “rule of eights” is valid for all sample sizes. Here we examine the analogous problem where the underlying distribution is exponential and find that a “rule of fours” yields optimality and prove the result rigorously. 相似文献
514.
The “marriageability of men” is an argument used in sociological research to understand demographic changes in marriage and to analyze social dynamics associated with gender, race, class, family, the workplace, incarceration, and more. While some are marrying later and others are foregoing marriage altogether, a lack of marriageable men is often part of the argument concerning new patterns of family formation in the United States. Research mobilizing the marriageability of men hypothesis spans a great deal of subfields of sociological research, not all in conversation with one another – and not all explicitly making use of the term. This article collects these diverse strands of thought and presents an argument for how and why men are less marriageable, what this means, and why it means different things for different groups of men and women. Racialized and classed conceptions of masculinity create different kinds of struggles for different groups of men and work against their marriageability for different reasons. We discuss the impact of incarceration, new struggles in a service economy, and shifts in women's perceptions and expectations of what qualifies men as “marriageable.” 相似文献
515.
Kent Christoph W. Lee Keunmin Ward Helen C. Hong Je-Woo Hong Jinkyu Gatey David Grimmond Sue 《Urban Ecosystems》2018,21(2):227-243
Urban Ecosystems - Local aerodynamic roughness parameters (zero-plane displacement, z d , and aerodynamic roughness length, z 0 ) are determined for an urban park and a suburban neighbourhood with... 相似文献
516.
Eschmann Rob Gryder Ryan W. Connaught Gerri Zhao Xiang Jeon Sae-Mi Gonzales Ernest 《Clinical Social Work Journal》2022,50(3):242-255
Clinical Social Work Journal - Experiences with more subtle racism – which have been called microaggressions – have a host of negative effects on health, mental health, educational... 相似文献
517.
Holly J. Payne Jennifer Mize Smith Kimberlee K. Everson Ganer L. Newman Iv 《Atlantic journal of communication》2019,27(1):30-45
Nonprofit organizations (NPOs) achieve desired outcomes by fostering organizational identification. However, little research has explored how identification with the cause or the recipients of support relates to identification with the NPO. This study developed the Identification with Social Causes Scale as a mechanism for distinguishing organizational identification from identification with a social group or cause. Data were collected using two groups: the homeless (n = 318) and HIV positive (n = 314) individuals. Exploratory factor analysis and multigroup confirmatory factor analysis yielded a 9-item scale measuring two dimensions: attachment and consubstantiality. Initial construct validity of the scale was established. 相似文献
518.
The goal of this study was to examine child and parent predictors of children's hostile attribution bias (HAB) with a particular focus on exploring the associations between parents’ early attribution of child misbehavior and children's HAB in the transition to school age. Participants were 241 children (118 girls) of middle‐income families who were at risk for school‐age conduct problems. Multi‐method, multi‐informant data were collected on maternal attributions of child misbehavior, parental use of corporal punishment, and child attributes (i.e., verbal IQ, effortful control, theory of mind, and emotional understanding) at 3 years, and child HAB in ambiguous situations at 6 years. Results indicated that mothers’ internal explanations for children's misconduct may either reduce or increase children's later HAB depending on the specific content of attributions, such that mothers’ belief that children misbehave because of their internal state (i.e., emotional state or temperament) was associated with lower levels of child HAB, whereas attributing power‐based motives (i.e., manipulative, controlling intentions) in children was associated with higher levels of HAB. The findings are discussed with respect to appreciating the complexity of parents’ explanations for children's behavior, and considering parental cognition as a potential target for early identification and prevention of child HAB and related problems. 相似文献
519.
Xinyun Wu Shengfeng Yan Xin Wan Zhipeng Lü 《Journal of Combinatorial Optimization》2016,32(2):445-468
The routing and wavelength assignment problem (RWA) has shown to be NP-hard if the wavelength continuity constraint and the objective of minimizing the number of wavelengths are considered. This paper introduces a multi-neighborhood based iterated tabu search algorithm (MN-ITS), which consists of three neighborhoods with a unified incremental evaluation method, to solve the min-RWA problem. The proposed MN-ITS algorithm is tested on a set of widely studied real world instances as well as a set of challenging random ones in the literature. Comparison with other reference algorithms shows that the MN-ITS algorithm is able to improve five best upper bounds obtained by other competitive reference algorithms in the literature. This paper also presents an analysis to show the significance of the unified incremental evaluation technique and the combination of multiple neighborhoods. 相似文献
520.
China??s oldest old population is estimated to quadruple by 2050. Yet, poverty rate for the oldest old has been the highest among all age groups in China. This paper investigates the relationship between economic stress, quality of life, and mortality among the oldest-old in China. Both objective economic hardships and perceived economic strain are examined. We base our investigation on data drawn from the Chinese Longitudinal Healthy Longevity Survey conducted between 2000 and 2005. Our sample includes 10,972 men and women between the ages of 80 and 105 in 2000. The data show that about 16% of these oldest-old lived under economic stress in 2000. The risk factors that make one vulnerable to economic stress include age, being male, being widowed or never married, being a minority member, having no education, having no living children, and not having children as main source of income, and having no pension. Economic stress is negatively associated with indicators of quality of life, such as the quality of medical care and mental well-being. The poor quality of life contributes to the higher mortality rate for the oldest old who are under economic stress. Results also show that perceived economic strain increases the risk of mortality by 42% in rural areas, even after controlling for basic demographic characteristics, life style factors, and major health events.?For the rural oldest-old, having children as a main source of income and having access to pension alleviates the negative impact of economic hardship on mortality hazard by 23 and 66% respectively. However, in urban areas, economic stress has no direct impact on the hazard of mortality. 相似文献