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11.
The choice of constraints in correspondence analysis   总被引:2,自引:0,他引:2  
A discussion of alternative constraint systems has been lacking in the literature on correspondence analysis and related techniques. This paper reiterates earlier results that an explicit choice of constraints has to be made which can have important effects on the resulting scores. The paper also presents new results on dealing with missing data and probabilistic category assignment.I am most grateful to the following for their helpful comments. Arto Demirjian, Michael Greenacre, Michael Healy, Shizuhiko Nishisato, Roderick Mcdonald, and several anonymous referees.  相似文献   
12.
This paper discusses thecompatibility of the polychotomous Rasch model with dichotomization of the response continuum. It is argued that in the case of graded responses, the response categories presented to the subject are essentially an arbitrary polychotomization of the response continuum, ranging for example from total rejection or disagreement to total acceptance or agreement of an item or statement. Because of this arbitrariness, the measurement outcome should be independent of the specific polychotomization applied, for example, presenting a specific multicategory response format should not affect the measurement outcome. When such is the case, the original polychotomous model is called compatible with dichotomization.A distinction is made between polychotomization or dichotomization before the fact, that is, in constructing the response format, and polycho- or dichotomization after the fact, for example in dichotomizing existing graded response data.It is shown that, at least in case of dichotomization after-the-fact, the polychotomous Rasch model is not compatible with dichotomization, unless a rather special condition of the model parameters is met. Insofar as it may be argued that dichotomization before the fact is not essentially different from dichotomization after the fact, the value of the unidimensional polychotomous Rasch model is consequently questionable. The impact of our conclusion on related models is also discussed.  相似文献   
13.
A direct method in handling incomplete data in general covariance structural models is investigated. Asymptotic statistical properties of the generalized least squares method are developed. It is shown that this approach has very close relationships with the maximum likelihood approach. Iterative procedures for obtaining the generalized least squares estimates, the maximum likelihood estimates, as well as their standard error estimates are derived. Computer programs for the confirmatory factor analysis model are implemented. A longitudinal type data set is used as an example to illustrate the results.This research was supported in part by Research Grant DAD1070 from the U.S. Public Health Service. The author is indebted to anonymous reviewers for some very valuable suggestions. Computer funding is provided by the Computer Services Centre, The Chinese University of Hong Kong.  相似文献   
14.
To examine the relationship between imitation and locomotor development among peers during infancy, we observed free play in a class of infants in a day-care center over a one-year period. The analysis included 16 infants (mean age was 8.3 months (SD=2.3) at the beginning of the observation) and 5 caregivers. The longitudinal data were divided into the crawling, cruising, and walking periods, and the imitation of object manipulation that took place among the infants during each period was analyzed. With the development of locomotion, peer-to-peer imitation became frequent. Infants who had acquired the ability to walk demonstrated imitation more frequently in triadic interactions than in dyadic interactions. Imitation took place between infants, but it was often mediated by caregivers rather than directly between infants. The results suggest that the acquisition of locomotor skills is a link in a developmental cascade from motor development to infant peer interaction. However, it is reasonable to interpret the results as indicating that the development of locomotion does not directly affect infant interactions in isolation, but rather that walking increases both the sharing and manipulation of objects with caregivers and proximity to peers, and their combined effects form a cascade.  相似文献   
15.
Applying the person-oriented approach to coping can provide a unique perspective by revealing typical latent patterns. The study examined typical latent patterns shown by task-, emotion- and avoidance-oriented trait-based coping styles. We performed secondary analyses with Latent Profile Analysis on our former data and three independent datasets containing coping measures with the CISS-48 scale (Endler & Parker, 1994). Gender differences were also studied. Two basic profiles seem universal: the first is characterized by a high level of task-oriented coping, and the second profile is with moderately high scores on all three coping styles. The finding indicates that two fundamental latent coping profiles exist, which suggests a within-subject comparison in practice instead of investigating the absolute value of coping styles. Comparing data before and after 2020, COVID-19 does not seem to affect these profiles. The person-centered approach provides a possibility for the integration of coping-related findings.  相似文献   
16.
研究发现学习效能感会受到同伴支持的影响,同时它又是影响学生学业状况的重要前因变量。根据控制价值理论,本研究通过对3329名高一和高二学生的调查,考察在物理和化学学科中,学习效能感是否会在同伴学业支持和学业情绪中起到中介作用。发现:(1)同伴学业支持和学习效能感呈显著正相关;两者与高兴学业情绪显著正相关,与厌倦学业情绪显著负相关;(2)在控制了年龄、年级、性别和地域后,学习效能感在同伴学业支持和高兴学业情绪中起部分中介作用,在同伴学业支持和厌倦学业情绪中起完全中介作用;(3)在物理学科中,性别调节了学习效能感和学业情绪的关系。本研究验证并拓展了控制价值理论,对于如何提高中学生物理和化学学习的积极情绪有借鉴意义。  相似文献   
17.
18.
Previous research has consistently found that unsociability is linked to adjustment difficulties in Chinese children. However, far less attention has been paid to how parents and peers react when confronted with unsociable children. In this study, we explored the longitudinal linkages among Chinese preschoolers' unsociability, maladaptive parenting, and peer exclusion. Participants were mothers and teachers of N = 391 (Mage = 4.4 years, SD = 0.91 years; 54.5% boys) preschoolers attending eight kindergartens in Shanghai, People's Republic of China, followed over 8 months. Multi-source assessments were employed. Mothers rated children's unsociability and their maladaptive (physical hostility, verbal hostility, punishment) parenting practices, and teachers rated children's peer exclusion at each time point. Our results indicated that child unsociability contributed to later increases in both maladaptive parenting and peer exclusion. However, maladaptive parenting and peer exclusion could not predict later increases in unsociability. Results are discussed in terms of the implications of unsociability among Chinese children.  相似文献   
19.
Ordinal data occur frequently in the social sciences. When applying principal component analysis (PCA), however, those data are often treated as numeric, implying linear relationships between the variables at hand; alternatively, non-linear PCA is applied where the obtained quantifications are sometimes hard to interpret. Non-linear PCA for categorical data, also called optimal scoring/scaling, constructs new variables by assigning numerical values to categories such that the proportion of variance in those new variables that is explained by a predefined number of principal components (PCs) is maximized. We propose a penalized version of non-linear PCA for ordinal variables that is a smoothed intermediate between standard PCA on category labels and non-linear PCA as used so far. The new approach is by no means limited to monotonic effects and offers both better interpretability of the non-linear transformation of the category labels and better performance on validation data than unpenalized non-linear PCA and/or standard linear PCA. In particular, an application of penalized optimal scaling to ordinal data as given with the International Classification of Functioning, Disability and Health (ICF) is provided.  相似文献   
20.
Raven's Advanced Progressive Matrices (APM) Set I is a validated and brief test of fluid intelligence, ideal for use in busy clinical settings. However, there is a dearth of normative data allowing an accurate interpretation of APM scores. To address this, we present normative data from across the adult lifespan (18–89 years) for the APM Set I. Data are presented in five age cohorts (total N = 352), including two older adult cohorts (65–79 years and 80–89 years), which allows age-standardized assessment. We also present data from a validated measure of premorbid intellectual ability, which was absent from previous standardizations of longer forms of the APM. In line with previous findings, a striking age-related decline was noted, beginning relatively early in adulthood and most marked amongst lower-scoring individuals. Older adults did not demonstrate difficulty with specific test items or make an increased proportion of specific errors. Sex was not a significant predictor of performance. The data set is of particular use in the neuropsychological assessment of older adults, given the known susceptibility of fluid intelligence to both the effects of normal ageing and acquired brain injury in older age. The results are discussed in light of theories of neurological ageing.  相似文献   
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