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861.
基于模拟研究比较了K-means方法、潜在类别模型和混合Rasch模型在二分外显变量情境下的聚类效果.结果表明:(1)潜在类别数量、变量数量、样本量、样本平衡和变量间相关对K-means方法、潜在类别模型和混合Rasch模型的分类准确性均有影响且因素间的交互作用存在;(2)除了在2个潜在类别的样本不平衡条件下K-means方法表现较差外,在其他条件下与潜在类别模型和混合Rasch模型的表现相当;(3)混合Rasch模型的分类一致性在2个潜在类别的情境下要好于潜在类别模型,但是在4个潜在类别的情境下要差于潜在类别模型. 相似文献
862.
One challenge in using naturalistic driving data is producing a holistic analysis of these highly variable datasets. Typical analyses focus on isolated events, such as large g-force accelerations indicating a possible near-crash. Examining isolated events is ill-suited for identifying patterns in continuous activities such as maintaining vehicle control. We present an alternative approach that converts driving data into a text representation and uses topic modeling to identify patterns across the dataset. This approach enables the discovery of non-linear patterns, reduces the dimensionality of the data, and captures subtle variations in driver behavior. In this study topic models were used to concisely described patterns in trips from drivers with and without untreated obstructive sleep apnea (OSA). The analysis included 5000 trips (50 trips from 100 drivers; 66 drivers with OSA; 34 comparison drivers). Trips were treated as documents, and speed and acceleration data from the trips were converted to “driving words.” The identified patterns, called topics, were determined based on regularities in the co-occurrence of the driving words within the trips. This representation was used in random forest models to predict the driver condition (i.e., OSA or comparison) for each trip. Models with 10, 15 and 20 topics had better accuracy in predicting the driver condition, with a maximum AUC of 0.73 for a model with 20 topics. Trips from drivers with OSA were more likely to be defined by topics for smaller lateral accelerations at low speeds. The results demonstrate topic modeling as a useful tool for extracting meaningful information from naturalistic driving datasets. 相似文献
863.
Ian Edelstein 《Journal of Psychology in Africa》2018,28(1):33-40
The aim of this study was to model pathways to violence propensity and violent behaviour among boys and young men in a high-violence community in South Africa. To that end, 284 young males (11 to 23 years old) from Khayelitsha, Cape Town self-reported risk for engagement in interpersonal violence and criminality; including within family, peer, and school domains, over a 12 month period. In Structural Equation Modelling, a pathway emerged through which an unstable home environment, influenced by deprivation and violence, affects the quality of parenting. In turn, early deviant associations and attitudes toward violence and gangs are cultivated and may have a deleterious effect on schooling, resulting in greater future substance abuse, greater violence propensity, and offending. These findings support the life course perspective approach, emphasising turning points and human agency in the aetiology of violence. 相似文献
864.
CAREGIVER SENSITIVITY AND CONSISTENCY AND CHILDREN'S PRIOR FAMILY EXPERIENCE AS CONTEXTS FOR EARLY DEVELOPMENT WITHIN INSTITUTIONS
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Brandi N. Hawk Robert B. Mccall Christina J. Groark Rifkat J. Muhamedrahimov Oleg I. Palmov Natalia V. Nikiforova 《Infant mental health journal》2018,39(4):432-448
The current study addressed whether two institution‐wide interventions in St. Petersburg, Russian Federation, that increased caregiver sensitivity (Training Only: TO) or both caregiver sensitivity and consistency (Training plus Structural Changes: T+SC) promoted better socioemotional and cognitive development than did a No Intervention (NoI) institution during the first year of life for children who were placed soon after birth. It also assessed whether having spent less than 9 versus 9 to 36 months with a family prior to institutionalization was related to children's subsequent socioemotional and cognitive development within these three institutions. The Battelle Developmental Inventory (J. Newborg, J.R. Stock, L. Wnek, J. Guidubaldi, & J. Svinicki, 1988) was used to assess the socioemotional and cognitive functioning of children in NoI (n = 95), TO (n = 104), and T+SC (n = 86) at two to three time points during their first 6 to 12 months of residency. Results suggest that improving caregiver sensitivity can improve the cognitive development of infants in the first year of institutionalization whereas improving caregiver consistency in addition to sensitivity is more beneficial for socioemotional development than is sensitivity alone. Similarly, for children in T+SC, longer time with a family prior to institutionalization (consistent caregiver, unknown sensitivity) was associated with better socioemotional, but not cognitive, baseline scores and more rapid cognitive than socioemotional development during institutionalization. These results suggest caregiver sensitivity is more highly related to cognitive development whereas caregiver consistency is more related to socioemotional development in the first years of life. 相似文献
865.
Johan H.L. Oud Manuel C. Voelkle Charles C. Driver 《Multivariate behavioral research》2018,53(1):36-56
This article explains in detail the state space specification and estimation of first and higher-order autoregressive moving-average models in continuous time (CARMA) in an extended structural equation modeling (SEM) context for N = 1 as well as N > 1. To illustrate the approach, simulations will be presented in which a single panel model (T = 41 time points) is estimated for a sample of N = 1,000 individuals as well as for samples of N = 100 and N = 50 individuals, followed by estimating 100 separate models for each of the one-hundred N = 1 cases in the N = 100 sample. Furthermore, we will demonstrate how to test the difference between the full panel model and each N = 1 model by means of a subject-group-reproducibility test. Finally, the proposed analyses will be applied in an empirical example, in which the relationships between mood at work and mood at home are studied in a sample of N = 55 women. All analyses are carried out by ctsem, an R-package for continuous time modeling, interfacing to OpenMx. 相似文献
866.
867.
The present research study sought to develop and validate a character scale – the Comprehensive Inventory of Virtuous Instantiations of Character using a total sample size of 3679 across five studies. In Study 1, character trait items were generated using an integrative classification system. In Study 2, character trait scales were further refined and their factor structure examined, revealing eight higher-order character dimensions or character cores: appreciation, intellectual engagement, fortitude, interpersonal consideration, sincerity, temperance, transcendence, and empathy. Study 3 established convergent validity of character traits with extant measures and discriminability from personality facets, social desirability, and moral cognitive development. Study 4 revealed that character cores were more strongly related to evaluative constructs than personality dimensions. Study 5 demonstrated that character cores predicted performance and psychological well-being outcomes above and beyond personality. The implications of our findings for the assessment and taxonomy of character are discussed. 相似文献
868.
The collection of very large text sources has revolutionized the study of natural language, leading to the development of several models of language learning and distributional semantics that extract sophisticated semantic representations of words based on the statistical redundancies contained within natural language (e.g., Griffiths, Steyvers, & Tenenbaum, 2007 ; Jones & Mewhort, 2007 ; Landauer & Dumais, 1997 ; Mikolov, Sutskever, Chen, Corrado, & Dean, 2013 ). The models treat knowledge as an interaction of processing mechanisms and the structure of language experience. But language experience is often treated agnostically. We report a distributional semantic analysis that shows written language in fiction books varies appreciably between books from the different genres, books from the same genre, and even books written by the same author. Given that current theories assume that word knowledge reflects an interaction between processing mechanisms and the language environment, the analysis shows the need for the field to engage in a more deliberate consideration and curation of the corpora used in computational studies of natural language processing. 相似文献
869.
No Evidence That Sleep Deprivation Effects and the Vigilance Decrement Are Functionally Equivalent: Comment on Veksler and Gunzelmann (2017)
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Erik M. Altmann 《Cognitive Science》2018,42(2):708-711
Veksler and Gunzelmann (2017) make an extraordinary claim, which is that sleep deprivation effects and the vigilance decrement are functionally equivalent. Extraordinary claims require extraordinary evidence, which is missing from Veksler and Gunzelmann's study. Their behavioral data offer only weak theoretical constraint, and to the extent their modeling exercise supports any position, it is that these two performance impairments involve functionally distinct underlying mechanisms. 相似文献
870.
A reappraisal of the relationship between span memory and intelligence via “best evidence synthesis” 总被引:1,自引:1,他引:0
This paper examines the relationship between span memory [e.g., immediate memory, short-term memory (STM), simple span] and general ability (g) though a reanalysis of two data sets [Christal, R. E. (1959). Factor analytic study of visual memory. Psychological Monographs: General and Applied, 72 (13, Whole No. 466); Kelley, H.P. (1964). Memory abilities: A factor analysis. Psychometric Monographs, No. 11]. Because of their large sample sizes and the multiple measures used to identify each construct, the Christal and Kelley studies were examined within a “best evidence synthesis” framework. Modern structural equation modeling (SEM) techniques were used to examine the relationship between immediate memory and g. Results indicated that in both studies, the relationship between immediate memory and g was quite substantial (.71 and .83), and that this relationship was essentially reduced by half when the common content variance of the tests was accounted for (e.g., verbal, spatial, numerical). Results are discussed within the context of recent research examining the relationship between working memory (WM) and g. 相似文献