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1.
This multi-method study sought to identify parameters of developmental change and stability of child reaction patterns to interparental conflict in the context of family relations in a sample of 223 6-year-old children and their parents followed over the course of one year. Consistent with the sensitization hypothesis, interparental withdrawal and hostility each consistently and uniquely predicted child distress reactions to conflict even after analytically controlling for parental warmth. Associations were found across multiple domains of child responding (i.e., overt negative affect, subjective negative affect, internal representations) and both concurrent and prospective, autoregressive analyses. Results of the autoregressive path analyses indicated moderate stability in each of the domains of conflict reactivity over the 1-year longitudinal period.  相似文献   

2.
Recent advances in statistical methodology, in particular, latent growth modeling, allow for the testing of complex models regarding developmental trends from both an inter‐ and intraindividual perspective. An example application of latent growth curve methodology, analyzing the effects of gender and parental monitoring on developmental change in adolescent alcohol consumption, is presented. Furthermore, the analyses are conducted within a cohort‐sequential design, incorporating an approach to the analysis of missing data due to attrition. Findings are discussed with particular reference to the utility of latent growth curve models for assessing developmental processes at both the inter‐and intraindividual level across a variety of behavioral domains.  相似文献   

3.
Latent growth curve models are widely used in the social and behavioral sciences to study complex developmental patterns of change over time. The trajectories of these developmental patterns frequently exhibit distinct segments in the studied variables. Latent growth models with piecewise functions for repeated measurements of variables have become increasingly popular for modeling such developmental trajectories. A major problem with using piecewise models is determining the precise location of the point where the change in the process has occurred and uncovering the related number of segments. The purpose of this paper is to introduce an optimization procedure that can be used to determine both the segments and location of the knots in piecewise linear latent growth models. The procedure is illustrated using empirical data in order to detect the number of segments and change points. The results demonstrate the capabilities of the procedure for fitting latent growth curve models.  相似文献   

4.
管壳式换热器流场数值模拟方法   总被引:2,自引:0,他引:2  
介绍了对管壳式换热器研究的基本方法。对数值模拟的优缺点和模拟的软件做了简要介绍,并对常用于管壳式换热器的两种方法:直接数值模拟和多孔介质模型两种类别作了明确阐述。  相似文献   

5.
Designers are required to plan for future expansion and also to estimate the grid's future utilization. This means that an effective modeling and forecasting technique, which will use efficiently the information contained in the available data, is required, so that important data properties can be extracted and projected into the future. This study proposes an adaptive method based on the multi-model partitioning algorithm (MMPA), for short-term electricity load forecasting using real data. The grid's utilization is initially modeled using a multiplicative seasonal ARIMA (autoregressive integrated moving average) model. The proposed method uses past data to learn and model the normal periodic behavior of the electric grid. Either ARMA (autoregressive moving average) or state-space models can be used for the load pattern modeling. Load anomalies such as unexpected peaks that may appear during the summer or unexpected faults (blackouts) are also modeled. If the load pattern does not match the normal behavior of the load, an anomaly is detected and, furthermore, when the pattern matches a known case of anomaly, the type of anomaly is identified. Real data were used and real cases were tested based on the measurement loads of the Hellenic Public Power Cooperation S.A., Athens, Greece. The applied adaptive multi-model filtering algorithm identifies successfully both normal periodic behavior and any unusual activity of the electric grid. The performance of the proposed method is also compared to that produced by the ARIMA model.  相似文献   

6.
The first part of this paper explains the distinction between proximal and distal causes of developmental disorders of cognition, with special reference to developmental disorders of reading. A number of different proximal causes of developmental disorders of reading have been identified. These correspond to a number of different patterns of developmental reading impairments – a number of “types of developmental dyslexia”, if you like – which are described in the second part of the paper. These patterns are interpreted in relation to a specific information-processing model of the cognitive system for reading. How each pattern is diagnosed, and how each might be treated, is discussed.  相似文献   

7.
This paper examines the limitations of standard scores of achievement tests commonly used in diagnosing learning disabilities. The consideration of these limitations is an important factor in attempting to decide whether a marked discrepancy exists between ability and achievemen, a requirement for the diagnosis of learning disabilities under Public Law 94–142. The phrase “standard score scale” is ambiguous because it can refer to both status score scales and developmental score scales. Unfortunately, many school psychologists seem unaware of the distinction between these two types of standard scores and the ramifications of this distinction. Many standardized achievement tests commonly used in the assessment of learning disabilities use status standard scores despite their severe limitations (noncomparability across grade levels and subjects, and failure to reflect changes in variability across grade levels). While developmental standard scores are to be preferred over status standard scores in diagnosing learning disabled children, their value is significantly lowered because they require greater growth for below-average students than for average or above-average students. Moreover, developmental scores are nonequal interval and they assume that subject matter is normally distributed within age or grade groups. Although we recommend the use of developmental standard scores over status standard scores, we urge that they be interpreted cautiously.  相似文献   

8.
This article presents a case for distinguishing between mental retardation as a general deficit of thinking and mental retardation that might result from the global effects of a specific deficit in a cognitive module. Using Anderson's (1992a) theory of the minimal cognitive architecture of intelligence and developmental, I show how this distinction can explain the pattern of intellectual strengths and weaknesses in Savant syndrome, Williams syndrome, Down syndrome, and autism. In addition, I discuss the developmental versus difference view and the distinction between organic and cultural familial mental retardation in the light of this theory. I conclude that not only is there no inherent incompatibility between the constructs of general intelligence and modularity of mind but that both are essential to understanding the different patterns of abilities and developmental profiles found in individuals with low IQ.  相似文献   

9.
Multilevel modeling has been utilized for combining single-case experimental design (SCED) data assuming simple level-1 error structures. The purpose of this study is to compare various multilevel analysis approaches for handling potential complexity in the level-1 error structure within SCED data, including approaches assuming simple and complex error structures (heterogeneous, autocorrelation, and both) and those using fit indices to select between alternative error structures. A Monte Carlo study was conducted to empirically validate the suggested multilevel modeling approaches. Results indicate that each approach leads to fixed effect estimates with little to no bias and that inferences for fixed effects were frequently accurate, particularly when a simple homogeneous level-1 error structure or a first-order autoregressive structure was assumed and the inferences were based on the Kenward-Roger method. Practical implications and recommendations are discussed.  相似文献   

10.
The present study followed a sample of first‐grade (= 316, Mage = 7.05 at first test) through fourth‐grade students to evaluate dynamic developmental relations between vocabulary knowledge and reading comprehension. Using latent change score modeling, competing models were fit to the repeated measurements of vocabulary knowledge and reading comprehension to test for the presence of leading and lagging influences. Univariate models indicated growth in vocabulary knowledge, and reading comprehension was determined by two parts: constant yearly change and change proportional to the previous level of the variable. Bivariate models indicated previous levels of vocabulary knowledge acted as leading indicators of reading comprehension growth, but the reverse relation was not found. Implications for theories of developmental relations between vocabulary and reading comprehension are discussed.  相似文献   

11.
This study investigated the developmental trajectories and interrelationships of mathematics-related achievement emotions and arithmetic fluency from first to third grade, and the effects of these on third grade mathematics performance. Participants were 232 Norwegian students. Students’ emotions and arithmetic fluency were measured four times and mathematics performance once. Applying latent growth curve modeling, developmental patterns of decreasing enjoyment and increasing boredom were observed over time. The mean level of enjoyment remained fairly high, and of both boredom and anxiety quite low. Individual differences were observed in both the initial levels and development of all emotions and arithmetic fluency, indicating differences in developmental trajectories. Only the initial levels and rate of change in arithmetic fluency predicted mathematics performance at the third grade.  相似文献   

12.
This Monograph aims to contribute to the information processing, the differential, and the developmental modeling of the mind, and to work these into an integrated theory. Toward this aim, a longitudinal study is presented that investigates the relations between processing efficiency, working memory, and problem solving from the age of 8 years to to the age of 16 years. The study involved 113 participants, about equally drawn among 8-, 10-, 12-, and 14-year-olds at the first testing; these participants were tested two more times spaced one year apart. Participants were tested with a large array of tasks addressed to processing efficiency (i.e., speed of processing and inhibition), working memory (in terms of Baddeley's model, phonological storage, visual storage, and the central executive of working memory), and problem solving (quantitative, spatial, and verbal reasoning). Confirmatory factor analysis validated the presence of each of the above dimensions and indicated that they are organized in a three-stratum hierarchy. The first stratum includes all of the individual dimensions mentioned above. These dimensions are organized, at the second stratum, in three constructs: processing efficiency, working memory, and problem solving. Finally, all second-order constructs are strongly related to a third-order general factor. This structure was stable in time. Structural equation modeling indicated that the various dimensions are interrelated in a cascade fashion so that more fundamental dimensions are part of more complex dimensions. That is, speed of processing is the most important aspect of processing efficiency, and it perfectly relates to the condition of inhibition, indicating that the more efficient one is in stimulus encoding and identification, the more efficient one is in inhibition. In turn, processing efficiency is strongly related to the condition of executive processes in working memory, which, in turn, is related to the condition of the two modality-specific stores (phonological and visual). Finally, problem solving is related to processing efficiency and working memory, the central executive in particular. All dimensions appear to change systematically with time. Growth modeling suggested that there are significant individual differences in attainment in each of the three aspects of the mind investigated. Moreover, each of the three aspects of the mind as well as their interrelations change differently during development. Mixture growth modeling suggested that there are four types of developing persons, each defined by a different combination of performance in these aspects of the mind. Some types are more efficient and stable developers than others. These analyses indicated that processing efficiency is a factor closely associated with developmental differences in problem solving, whereas working memory is associated with individual differences. Modeling by logistic equations uncovered the rates and form of change in the various dimensions and their reciprocal interactions during development. These findings are discussed from the point of view of information processing, differential, and developmental models of thinking, and an integrative model is proposed.  相似文献   

13.
ABSTRACT

This article reports a graduate level program designed to facilitate inquiry into the integration of technology in schools (ITS). The ITS Process is described within the frame of insights related to teacher developmental readiness for change. The process of teacher education is viewed as change within the dialectic of ideas and actions built around the dynamics of reflection, experience, modeling, planning, and a return to reflection. Four domains of inquiry, the building of a community of thinkers, a broad base of collaboration, and transdisciplinary study are presented as the foundation of the ITS Process. A four semester process of study and the concomitant curriculum are outlined, and strategies for facilitating the process are explored.  相似文献   

14.
现代装饰画与传统装饰画的区别,主要体现在他不再是时间意义上的现代,而是意义上的创新,出现了与美相悖的装饰画作品内容,其名称的界定变得模糊了,并且形式和内容倾向于理论化,造型倾向于抽象化。  相似文献   

15.
Despite the widespread enthusiasm towards grit, little attention has been paid to how stable grit remains over time and what contextual factors can predict longitudinal changes in grit. The present study investigated adolescent students’ grit and its change over one year. We employed nationally representative longitudinal data from a sample of Korean adolescent students (N = 2,590) and their parents (N = 2,590). Specifically, we evaluated the temporal stability of student grit, parent grit and educational expectations as determinants of student grit, and the relative importance of student grit in predicting academic achievement compared to academic self-concept. Results of autoregressive cross-lagged modeling revealed that grit was fairly stable over one year. In addition, parents’ grit and educational expectations for students’ educational attainment emerged as significant predictors of longitudinal changes in students’ grit. Finally, when students’ academic self-concept was controlled, students’ grit was not predictive of their academic achievement. Implications and areas of future research are presented and discussed.  相似文献   

16.
To infer longitudinal relationships among latent factors, traditional analyses assume that the measurement model is invariant across measurement occasions. Alternative to placing cross-occasion equality constraints on parameters, approximate measurement invariance (MI) can be analyzed by specifying informative priors on parameter differences between occasions. This study evaluated the estimation of structural coefficients in multiple-indicator autoregressive cross-lagged models under various conditions of approximate MI using Bayesian structural equation modeling. Design factors included factor structures, conditions of non-invariance, sizes of structural coefficients, and sample sizes. Models were analyzed using two sets of small-variance priors on select model parameters. Results showed that autoregressive coefficient estimates were more accurate for the mixed pattern than the decreasing pattern of non-invariance. When a model included cross-loadings, an interaction was found between the cross-lagged estimates and the non-invariance conditions. Implications of findings and future research directions are discussed.  相似文献   

17.
The distinction between general early childhood education and special education on the issue of the essential characteristics of play, developmental appropriateness, and an emphasis on teacher directiveness, external contingencies, and correct products may help explain the relatively small body of work focused on teaching preschool children with developmental concerns how to appropriately engage in play with toys. Appropriately designed intervention is not only compatible with the concept of play, many children require intervention to support their continued development. The purpose of this paper is to explore the applied research in which object-related play skills of preschool children with developmental concerns are enhanced through intervention strategies. Guidelines for teaching toy play will be presented and strategies to promote generalisation and maintenance will be discussed.  相似文献   

18.
Associations between experiencing child maltreatment and adverse developmental outcomes are widely studied, yet conclusions regarding the extent to which effects are bidirectional, and whether they are likely causal, remain elusive. This study uses the Fragile Families and Child Wellbeing Study, a birth cohort of 4,898 children followed from birth through age 9. Hierarchical linear modeling and structural equation modeling are employed to estimate associations of maltreatment with cognitive and social‐emotional well‐being. Results suggest that effects of early childhood maltreatment emerge immediately, though developmental outcomes are also affected by newly occurring maltreatment over time. Additionally, findings indicate that children's early developmental scores predict their subsequent probability of experiencing maltreatment, though to a lesser extent than early maltreatment predicts subsequent developmental outcomes.  相似文献   

19.
Latent growth curve modeling employed data from a longitudinal study of 451 sibling families to examine parents, siblings, and family economics as factors in individual differences in the developmental course of interpersonal aggression during adolescence. Findings suggest that individual change in interpersonal aggression during adolescence can be predicted by the gender and aggression of one's sibling; predictions varied by the gender composition of the sibling dyad. Rates of parental hostility predicted levels of interpersonal aggression for both older (mean age = 12 years) and younger siblings (mean age = 15), and growth in aggression for younger siblings. Family economic pressure predicted interpersonal aggression of both siblings indirectly through parental hostility. Implications for future research and preventive interventions are discussed.  相似文献   

20.
Several papers have been devoted to the use of structural equation modeling (SEM) software in fitting autoregressive moving average (ARMA) models to a univariate series observed in a single subject. Van Buuren (1997) went beyond specification and examined the nature of the estimates obtained with SEM software. Although the results were mixed, he concluded that these parameter estimates resemble true maximum likelihood (ML) estimates. Molenaar (1999) argued that the negative findings for pure moving average models might be due to the absence of invertibility constraints in Van Buuren's simulation experiment. The aim of this article is to (a) reexamine the nature of SEM estimates of ARMA parameters; (b) replicate Van Buuren's simulation experiment in light of Molenaar's comment; and (c) examine the behavior of the log-likelihood ratio test. We conclude that estimates of ARMA parameters obtained with SEM software are identical to those obtained by univariate stochastic model preliminary estimation, and are not true ML estimates. Still, these estimates, which may be viewed as moment estimates, have the same asymptotic properties as ML estimates for pure autoregressive (AR) processes. For pure moving average (MA) processes, they are biased and less efficient. The estimates from SEM software for mixed processes seem to have the same asymptotic properties as ML estimates. Furthermore, the log-likelihood ratio is reliable for pure AR processes, but this is not the case for pure MA processes. For mixed processes, the behavior of the log-likelihood ratio varies, and in this case these statistics should be handled with caution.  相似文献   

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