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141.
Early in development, children explore and combine objects in increasingly complex ways. One manual skill, object construction, represents a major shift in how objects are explored relative to other objects. Despite recent connections with cognitive functioning such as spatial skills, the development of object construction ability has rarely been studied and its trajectory has not been adequately described. The purpose of this study was to describe the development of three types of object construction (stacking, nesting, and affixing) across 5 monthly infant visits and 7 monthly toddler visits using a longitudinal design and a large sample size. Infants (10–14 months, n = 131) and toddlers drawn from the infant sample (18–24 months, n = 65) were given sets of age‐appropriate toys each of which elicited at least one type of constructive play. We described success at different construction tasks and identified trends for construction skill for infant and toddler development using multilevel modeling. We found that each of the three construction actions developed in unique ways across the 10‐ to 24‐month period. Infant construction skill predicted the development of toddler skill, but toddler construction skill diverged from infant trajectories. We discuss the role of combination strategies in the development of object construction skill and how object construction could be related to other domains of development. 相似文献
142.
A random effects model for analyzing mixed longitudinal count and ordinal data is presented where the count response is inflated in two points (k and l) and an (k,l)-Inflated Power series distribution is used as its distribution. A full likelihood-based approach is used to obtain maximum likelihood estimates of parameters of the model. For data with non-ignorable missing values models with probit model for missing mechanism are used.The dependence between longitudinal sequences of responses and inflation parameters are investigated using a random effects approach. Also, to investigate the correlation between mixed ordinal and count responses of each individuals at each time, a shared random effect is used. In order to assess the performance of the model, a simulation study is performed for a case that the count response has (k,l)-Inflated Binomial distribution. Performance comparisons of count-ordinal random effect model, Zero-Inflated ordinal random effects model and (k,l)-Inflated ordinal random effects model are also given. The model is applied to a real social data set from the first two waves of the national longitudinal study of adolescent to adult health (Add Health study). In this data set, the joint responses are the number of days in a month that each individual smoked as the count response and the general health condition of each individual as the ordinal response. For the count response there is incidence of excess values of 0 and 30. 相似文献
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Heather T. Rowan‐Kenyon Amy K. Swan Marie F. Creager 《The Career development quarterly》2012,60(1):2-15
The authors examined the central hypothesis that students’ early perceptions of support and sense of engagement in math classes and math activities strongly influence the broadening or narrowing of their math interest. The focus was on the first wave of qualitative data collected from 5th‐, 7th‐, and 9th‐grade students during the 2007–2008 academic year as part of a longitudinal study. Findings indicate the importance of using group work and extrinsic motivation in middle school math classes to broaden interest; peer classroom behavior was often a detractor of math interest. 相似文献
145.
Philip Looper David George Eric J. Johnson Susan E. Conway 《Journal of American college health : J of ACH》2017,65(7):513-517
Objective: To examine the perceptions among faculty and health professional students regarding mandatory vaccination policies on a health sciences campus. Participants: A total of 296 faculty and 244 students completed surveys during Fall 2015. Methods: The online survey administered to individuals who received the influenza vaccine during the fall 2015 influenza vaccination clinic season included five items evaluating perceptions of employer mandatory vaccination requirements. Results: Chi-square analysis indicated that although faculty and students agree mandatory vaccinations in a health care environment are appropriate, faculty are more likely than students to get vaccinated in the absence of a mandate. Additionally, a small fraction of faculty would consider employment elsewhere when facing this mandate. Conclusions: Overall, faculty and students had favorable perceptions about mandatory influenza vaccine policies. Since students were less likely to be vaccinated in the absence of a mandate, education of students should be improved to support the importance of vaccinations in a health care environment. 相似文献
146.
The estimated vector autoregressive (VAR) model is sensitive to model misspecifications, resulting to biased and inconsistent parameter estimates. This article extends the Bayesian averaging of classical estimates, a robustness procedure in cross-section data, to a vector time-series that is estimated using a large number of asymmetric VAR models. The proposed procedure was applied to simulated data from various forms of model misspecifications. The results of the simulation suggest that, under misspecification problems, particularly if an important variable and moving average (MA) terms were omitted, the proposed procedure gives robust results and better forecasts than the automatically selected equal lag-length VAR model. 相似文献
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Tyler J. Smith Rebecca A. Lindsey Som Bohora Jane F. Silovsky 《Journal of sex research》2019,56(2):229-238
Intrusive sexual behaviors (ISBs) are a specific type of problematic sexual behavior characterized by the invasive nature of the acts (e.g., touching others’ private parts, attempting intercourse; Friedrich, 1997). The limited amount of research on ISBs has focused on sexual abuse history as the primary predictor. However, Friedrich, Davies, Feher, and Wright (2003) found that ISBs in children up to age 12 were related to four broad conceptual factors: (a) exposure to sexual content, (b) exposure to violent behavior, (c) family adversity, and (d) child vulnerabilities. The current study sought to replicate Friedrich’s study using a clinical sample of 217 preschool-aged children (ages two to six). Results supported variables from within the child vulnerabilities construct (externalizing behaviors, βEXT = 0.032, p = 0.001), post-traumatic stress disorder (PTSD) criteria met (βPTSD = 0.177, p = 0.02), and an inverse relationship with age (βAGE = ?0.206, p = 0.024). These results highlight the importance of considering childhood behavioral patterns and reactivity to traumatic events as correlates of ISBs in young children. 相似文献
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The aim of this study was to investigate the role of drinking in two Norwegian workplaces, focusing on how the drinking may contribute to both social integration and marginalization of employees. The two workplaces were a division of a multinational oil company and a public library both located in one of Norway's larger cities. Data were collected through ethnographic fieldwork, including using participant observation, qualitative interviews, and brief surveys. Work-related drinking was found to be common in both workplaces and played a significant role in a wide range of social situations in the twilight zone between normal working hours and leisure. Drinking was regulated by dominant workplace alcohol cultural ideals, but also involved opposition to these ideals. The results of this study have demonstrated that different forms of drinking (and non-drinking) may lead to both social integration and marginalization – or even exclusion of groups of employees or individual employees. 相似文献