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241.
Analysis of 1998 statistics for individual performance in the PGA European Tour yielded significant differences between some shot-making skills (drive distance, total driving, greens in regulation, and sand saves) between the top 10 and bottom 10 money winners, replicating (with partially different results) a result found for the 1995 American PGA Tour by Engelhardt.  相似文献   
242.
This study examined the relations between maternal criticism and externalizing and internalizing symptoms in adolescents who varied in their risk for psychopathology. Both maternal-effects and child-effects models were examined. The sample consisted of 194 adolescents (mean age = 11.8~years) and their mothers; 146 mothers had a history of depressive disorders and 48 did not. When adolescents were in 6th and 8th grade, maternal criticism was measured with the five-minute speech sample and adolescents symptoms were assessed with the Child Behavior Checklist. Maternal criticism was significantly associated with both adolescents externalizing and internalizing symptoms, beyond the contribution of the chronicity/severity of mothers depression history. Maternal criticism did not mediate the relation between maternal depression and adolescent symptoms. In contrast, adolescent externalizing behaviors mediated the relation between chronicity/severity of maternal depression history and maternal criticism in 6th grade. Prospective analyses showed that adolescents externalizing symptoms in 6th grade significantly predicted maternal criticism in 8th grade, controlling for maternal depression history and prior maternal criticism. Results are discussed in terms of the importance of examining child-effects models in studies of maternal criticism.  相似文献   
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Previous research suggests that early mentoring relationship (MR) closures may have harmful consequences for the health and well‐being of youth participating in community‐based mentoring programs. However, knowledge of the factors that lead some MRs to close early has been slow to emerge. This study examined patterns and correlates of early versus on‐time MR closures among 569 youth participating in Big Brothers Big Sisters community mentoring programs. Thirty‐four percent of youth experienced an early MR closure prior to the end of the program's 12 month period of commitment. The probability of closure was highest at 12 months into the MR. Early closures were positively associated with youth gender (girls), behavioral difficulties, and match determination difficulties. Early and on‐time closures were associated with youth extrinsic motives for joining the program. Early MR closures were negatively associated with youth perceptions of parent emotional support, parent social support, high quality MR, weekly contact in MR, and parent support of the MR. Implications for programming are discussed.  相似文献   
245.
In executing purposeful actions, adults select sufficient and necessary limbs. But infants often move goal‐irrelevant limbs, suggesting a developmental process of motor specialization. Two experiments with 9‐ and 12‐month‐olds revealed gradual decreases in extraneous movements in non‐acting limbs during unimanual actions. In Experiment 1, 9‐month‐olds produced more extraneous movements in the non‐acting hand/arm and feet/legs than 12‐month‐olds. In Experiment 2, analysis of the spatiotemporal dynamics of infants’ movements revealed developmental declines in the spatiotemporal coupling of movements between acting and non‐acting arms. We also showed that the degree of specialization in infants’ unimanual actions is associated with individual differences in motor experience and visual attention, indicating the experience‐dependent and broad functional nature of these developmental changes. Our study provides important new insights into motor development: as in cognitive domains, motor behaviours are initially broadly tuned to their goal, becoming progressively specialized during the first year of life.  相似文献   
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Resumen

En el presente trabajo se han empleado las medidas cronométricas de Tiempo de Inspección (TI) y Tiempo de Reacción (TR) para estudiar los efectos de las diferencias individuales en extroversion sobre una tarea de discriminación perceptual. Para ello se utilizaron dos grupos de sujetos que habían obtenido puntuaciones máximas y mínimas en la dimensión Extraversión del Test EPI de H. J. Eysenck. Se postuló que los extrovertidos obtendrían un TI más corto que los introvertidos y asimismo un TR también más corto, de acuerdo a los modelos de Brebner (1980) y Tous (1986). Los resultados indicaron que si bien existieron diferencias entre extrovertidos e introvertidos en cuanto a las medidas cronométricas, estas dit erencias dependieron del uso diferencial de estrategias de resolver la tarea que fueron utilizadas por estos sujetos.  相似文献   
248.
The purpose of this study was to examine an integrated model of the work–family interface (WFI) linking work–family demands (workload and family conflict), resources (supervisory support and family support) and role satisfaction in a Chinese context. The four‐factor structure of WFI comprises direction of influence (work to family vs family to work) and types of effect (work–family conflict vs work–family enrichment). A longitudinal design was used to collect data from 409 Chinese employees at three time points, separating measures of antecedents (T1), WFI (T2) and outcomes (T3) in time. The results based on structural equation modelling (SEM) reveal that: (1) the direction and types of effect were two underlying dimensions of the WFI, supporting the four‐factor structure; (2) demands were more strongly related to conflict, while resources were more strongly related to enrichment; (3) work–family conflict and enrichment were related to role satisfaction, regardless of the direction of influence.  相似文献   
249.
This paper demonstrates the usefulness and flexibility of the general structural equation modelling (SEM) approach to fitting direct covariance patterns or structures (as opposed to fitting implied covariance structures from functional relationships among variables). In particular, the MSTRUCT modelling language (or syntax) of the CALIS procedure (SAS/STAT version 9.22 or later: SAS Institute, 2010) is used to illustrate the SEM approach. The MSTRUCT modelling language supports a direct covariance pattern specification of each covariance element. It also supports the input of additional independent and dependent parameters. Model tests, fit statistics, estimates, and their standard errors are then produced under the general SEM framework. By using numerical and computational examples, the following tests of basic covariance patterns are illustrated: sphericity, compound symmetry, and multiple‐group covariance patterns. Specification and testing of two complex correlation structures, the circumplex pattern and the composite direct product models with or without composite errors and scales, are also illustrated by the MSTRUCT syntax. It is concluded that the SEM approach offers a general and flexible modelling of direct covariance and correlation patterns. In conjunction with the use of SAS macros, the MSTRUCT syntax provides an easy‐to‐use interface for specifying and fitting complex covariance and correlation structures, even when the number of variables or parameters becomes large.  相似文献   
250.
This study examined, in a sample of recently immigrated Hispanic adolescents in Miami and Los Angeles, the extent to which bicultural identity integration (BII; involving the ability to synthesise one's heritage and receiving cultural streams and to identify as a member of both cultures) is best understood as a developmental construct that changes over time or as an individual‐difference construct that is largely stable over time. We were also interested in the extent to which these trajectories predicted mental health and family functioning. Recent‐immigrant 9th graders (N = 302) were assessed 6 times from 9th to 12th grade. Latent class growth analyses using the first 5 timepoints identified 2 trajectory classes—one with lower BII scores over time and another with higher BII scores over time. Higher heritage and US identity at baseline predicted membership in the higher BII class. At the 6th study timepoint, lower BII adolescents reported significantly poorer self‐esteem, optimism, prosocial behaviour and family relationships compared with their higher BII counterparts. These findings are discussed in terms of further research on the over‐time trajectory of biculturalism, and on the need to develop interventions to promote BII as a way of facilitating well‐being and positive family functioning.  相似文献   
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