Mediation Model Of Effects Research Articles

Maturational timing, physical self-perceptions and physical activity in UK adolescent females: investigation of a mediated effects model

Background Advanced (early) biological maturation may be a risk factor for inactivity among adolescent girls. Aim To test the mediational effects of body attractiveness and physical self-worth on the relationship between biological maturity and accelerometer assessed moderate-to-vigorous physical activity (MVPA) in a large multi-ethnic sample of girls from the Midlands area in the UK (11–14 years). Subjects and methods Biological maturity (predicting age at peak height velocity (APHV)); self-perceptions of body attractiveness, physical self-worth, and minutes spent in MVPA were assessed in 1062 females aged 11–14 years. Results Structural equation modelling using maximum likelihood estimation and boot- strapping procedures supported the hypothesised model. Later maturation predicted higher perceptions of body attractiveness (β = 0.25, p < .001) which, in turn, predicted higher perceptions of physical self-worth (β = 0.91, p < .001) and, significantly higher MVPA (β = 0.22, p < .001). Examination of the bootstrap-generated bias-corrected confidence intervals suggested that perceptions of body attractiveness and physical self-worth partially mediated a positive association between predicted APHV and MVPA (β = 0.05, p < .001). Conclusions Greater biological maturity (i.e. early maturity) in adolescent girls is associated with less involvement in MVPA and appears to be partly explained by lower perceptions of body attractiveness and physical self-worth. Physical activity interventions should consider girls' perceptions of their pubertal related physiological changes during adolescence, particularly among early maturing girls.

Physical Activity Mediates the Relationship between Gait Function and Fall Incidence after Total Knee Arthroplasty.

The present study aims to examine (1) the preoperative factors that can predict postoperative falls, (2) whether postoperative physical activity (PA) mediates the relationship between fall incidence and gait function, and (3) whether postoperative PA levels are associated with fall risk in total knee arthroplasty (TKA) patients. Ninety-six patients (mean age: 72.0 ± 6.1 years) who were observed postoperatively for 6 months were selected. Timed up and go (TUG) was assessed as an indicator of gait function. Fall incidence and PA were investigated for 6 months post-TKA. The body mass index, history of preoperative falls, knee pain, knee extensor strength, range of motion in knee flexion, and modified gait efficacy scale were evaluated. Additionally, postoperative PA levels were categorized into three groups-low: <3,000, moderate: 3,000 to 4,000, and high: ≥4,000 steps/day. The relative fall incidence rate was calculated according to the total number of falls normalized for every 1,000 steps/day for 6 months postoperatively. Twenty-five (26.0%) of the 96 patients had at least one fall. The TUG, knee pain, and knee extensor strength were identified preoperatively as significant variables affecting postoperative falls. The mediated effects model revealed that postoperative fall incidence was predicted by preoperative TUG and postoperative PA. Postoperative PA was significantly associated with preoperative TUG. Moreover, both the preoperative TUG and postoperative PA were selected as significant variables for predicting fall incidence. Thus, postoperative PA mediates the relationship between gait function and fall incidence after TKA. Furthermore, the relative fall incidence rate associated with a low PA level was significantly higher than that associated with moderate and high PA levels. In conclusion, preoperative assessments of TUG performance, muscle strength, and knee pain were effective in predicting fall risk. Additionally, an increase in PA could contribute to reducing fall risk in TKA patients. Therefore, our results suggest that preoperative screening for fall predictors and managing postoperative PA could reduce the fall incidence in TKA patients.

校長促進教師專業學習的槓桿：校長學習領導對教師課堂教學研究影響之中介模式分析 The Leverage for Principals to Promote Teacher Professional Learning: Analyzing a Mediated-effects Model Regarding the Impact of Principal Leadership for Learning on Lesson Study

校長促進教師專業學習的槓桿：校長學習領導對教師課堂教學研究影響之中介模式分析 The Leverage for Principals to Promote Teacher Professional Learning: Analyzing a Mediated-effects Model Regarding the Impact of Principal Leadership for Learning on Lesson Study

Principal Instructional Leadership, Teacher Self-Efficacy, and Teacher Professional Learning in China: Testing a Mediated-Effects Model

Background: Empirical evidence increasingly suggests that leadership which motivates, supports, and sustains the professional learning of teachers has a knock-on effect for both student learning and school improvement. The current study was conducted in China, where the workplace learning of teachers is embedded in a strong tradition of school-based, teacher learning practices such as the Master Teacher–Apprentice Bond and Teacher Research Groups. Purpose: The study investigated a mediated-effects model of principal instructional leadership and teacher learning. The model proposed principal time management skills and self-efficacy as antecedents of instructional leadership and teacher self-efficacy as a mediator of principal instructional leadership effects on the professional learning of teachers. Method: Survey data were collected from 3,414 teachers and 186 principals in 186 middle schools in Qingdao, China. Confirmatory factor analysis, structural equation modeling, and bootstrapping were used to analyze the multisource data. Results: The research confirmed a partial mediation model whereby principal instructional leadership evidenced moderate direct and indirect effects on teacher professional learning. Principal time management and self-efficacy exercised small effects on principal instructional leadership. Implications: The research adds to a growing body of research that affirms a positive relationship between principal leadership and teacher professional learning and emphasizes the importance of self-efficacy in shaping educator practice. The authors suggest the timeliness for scholars to undertake systematic reviews of this literature on leadership and teacher professional learning, and offer recommendations for school leadership practice.

School leadership and its impact on student achievement

Purpose– The purpose of this paper is to examine the role of teacher job satisfaction and school climate in mediating the relative effects of principals’ instructional and transformational leadership practices on student outcomes.Design/methodology/approach– Guided by strong evidence from theories on school leadership and work psychology, the authors hypothesized relations among dimensions of principals’ instructional and transformational leadership behaviors, teachers’ perception of the school climate (social and affective, and physical environment), their job satisfaction and student achievement. The benefits of the principal’s leadership behaviors for student achievement are primarily hypothesized as indirect, with either a weak or statistically non-significant direct positive effect on student outcomes. Path modeling was applied to validate a mediated-effects model using cross-sectional survey data (306 principals, 1,539 teachers) obtained from 306 secondary schools in the two Indian metropolitan cities of New Delhi and Kolkata.Findings– Principal leadership behaviors were not associated directly with either teacher job satisfaction or school-aggregated student achievement. Rather, the transformational leader behavior showed an indirect effect, through the social and affective component of the school climate, on teacher job satisfaction. The physical climate, however, appeared to play a dominating role in mediating the instructional leadership effects on teacher job satisfaction. Comparing the relative indirect effect sizes of the instructional and transformational leadership behaviors on student achievement, principals appear to favor the former approach.Originality/value– This study provides further empirical evidence that instructional leadership better captures the impact of school leadership on student outcomes, when compared to its transformational counterpart. By identifying the relative effects of different leadership practices, school leaders and educational practitioners can focus more on altering the distribution and frequency of those practices that work best for ameliorating student achievement levels.

The Impact of Principal Perception on Student Academic Climate and Achievement in High School: How Does it Measure Up?

The purpose of this study is to examine the independent direct effects of student and principal perceptions of academic climate on student achievement in high school. To date, few studies have considered the influence of principal perceptions of academic climate on student achievement. In the present study, we test a set of two-level hierarchical linear models using the large, nationally representative Education Longitudinal Study of 2002 to examine the independent effects of principal and student perceptions of academic climate on student achievement in mathematics, controlling for leadership and student and school background and context variables. Results suggest that principal perception of academic climate may have a direct effect on student achievement. Combining these results with the recent literature, we propose a mediated effects model of principal perceptions of leadership on student achievement.

Exploring the relationship among principals supervision of instruction, teachers' knowledge sharing and teachers' professional development: A test of the mediated-effects model

This study aims to analyze the relationship between principal's supervision of instruction, teachers' knowledge sharing and teachers' professional development by using mediated-effects model. Previous studies normally use directed-effects model. However, the use of directed-effects model does not resolve the most important theoretical issues concerning the means by which principals achieve an impact on teachers' professional development through teachers' knowledge sharing. Therefore, we use mediated-effects model to analyze the relationship in this study. By using product-moment correlation, regression analysis and the structural equation modeling (SEM), this study examined the relationship between principal's supervision of instruction and teachers' professional development mediated by the condition of knowledge sharing. Three related questionnaires were used to measure the major variables while data was collected of teachers in Pingtung County. It was found that principal's supervision of instruction can predict teachers' knowledge sharing and principal's supervision of instruction and teachers' knowledge sharing can also predict teachers' professional development. Also, the result from mediated-effects model indicated that knowledge sharing had the significant mediated effects of supervision of instruction on teachers' professional development.

Modeling the Influence of School Leaders on Student Achievement

Purpose: The aim of this study was to examine the means by which principals achieve an impact on student achievement. Research Design: Through the application of structural equation modeling, a mediated-effects model for school leadership was tested, using data from 97 secondary schools in the Netherlands. Findings: The results showed a small positive effect of school leadership on the mean promotion rate in schools, mediated by a development-oriented school organization and favorable classroom practices. The promotion rate may be considered as a measure of efficiency. No indications of direct positive effects of school leader activities on student achievement were found. This might be the result of the relatively small differences in overall student achievement and school leader behavior between the schools studied. Conclusions: The results underline the important role school leaders play in school effectiveness and offer valuable insight in how school leaders actually can make a difference. School leaders were found to have a strong influence on development orientation in schools, which shows similarities with the idea of the “learning organization.” This study points to the importance of school context. The results show that contextual variables have considerable effects on several variables in the model.

Maturity Associated Variance in Physical Activity and Health-Related Quality of Life in Adolescent Females: A Mediated Effects Model

This study tested a mediated effects model of psychological and behavioral adaptation to puberty within the context of physical activity (PA). Biological maturity status, physical self-concept, PA, and health-related quality of life (HRQoL) were assessed in 222 female British year 7 to 9 pupils (mean age = 12.7 years, SD = .8). Structural equation modeling using maximum likelihood estimation and bootstrapping procedures supported the hypothesized model. Maturation status was inversely related to perceptions of sport competence, body attractiveness, and physical condition; and indirectly and inversely related to physical self-worth, PA, and HRQoL. Examination of the bootstrap-generated bias-corrected confidence intervals representing the direct and indirect paths between suggested that physical self-concept partially mediated the relations between maturity status and PA, and maturity status and HRQoL. Evidence supports the contention that perceptions of the physical self partially mediate relations maturity, PA, and HRQoL in adolescent females.

Does High School Facility Quality Affect Student Achievement?: A Two-Level Hierarchical Linear Model

The purpose of this study is to isolate the independent effects of high school facility quality on student achievement using a large, nationally representative U.S. database of student achievement and school facility quality. Prior research on linking school facility quality to student achievement has been mixed. Studies that relate overall independently rated structural and engineering aspects of schools have been shown to not be related to achievement. However, more recent research has suggested that facility maintenance and disrepair, rather than structural issues, may be more directly related to student achievement. If there is a relationship, addressing facility disrepair from the school, district, or state level could provide a potential avenue for policymakers for school improvement. We analyzed the public school component and the facilities checklist of the ELS:2002 survey (8,110 students in 520 schools) using a two-level hierarchical linear model to estimate the independent effect of facility disrepair on student growth in mathematics during the final two years of high school controlling for multiple covariates at the student and school level. We found no evidence of a direct effect of facility disrepair on student mathematics achievement and instead propose a mediated effects model.

The mediating role of physical self-concept on relations between biological maturity status and physical activity in adolescent females

The current study examined the mediating role of physical self-concept on relations between biological maturity status and self-reported physical activity in adolescent British females. Biological maturity status, physical self-concept and physical activity were assessed in 407 female British year 7–9 pupils (M age = 13.2 years, SD = 1.0). Participants completed the Physical Activity Questionnaire for Adolescents (Kowalski, Crocker, & Donen, 2004) and the Children and Youth Physical Self-Perceptions Profile (Whitehead, 1995). Percentage of predicted adult height attained at measurement was used as an estimate of biological maturity status. Structural equation modelling using maximum likelihood estimation and bootstrapping procedures revealed that perceptions of sports competence, body attractiveness and physical self-worth mediated an inverse relation between maturity status and physical activity. The results provide partial support for Petersen and Taylor’s (1980) Mediated Effects Model of Psychological and Behavioural Adaptation to Puberty within the context of physical activity.

Does sponsorship work in the same way in different sponsorship contexts?

PurposeThe purpose of this paper is to develop a comprehensive model of high‐level sponsorship effects that works well in both sports and cultural sponsorship contexts.Design/methodology/approachThe sponsorship model is tested using survey data from target market representative samples in two professional sports contexts and two cultural contexts.FindingsThe model works almost equally well in both contexts. Furthermore, a more parsimonious mediated effects model provides virtually the same results as the full model. Improving attitude towards the sponsorship and object equity are found to be the most important factors for improving sponsor equity. The model also confirms earlier research on the importance of sponsor sincerity and sponsor‐object fit in determining sponsorship effects.Research limitations/implicationsThe explained variance of the sincerity and object equity constructs was not as high as for other constructs in the model.Practical implicationsSponsorship managers should pre‐test potential objects and sponsorship communications to make sure that constructs in the model such as fit, sincerity, sponsorship attitudes, and object equity are maximised to provide optimal sponsor equity.Originality/valueThe model combines constructs from various literatures into a comprehensive model of high‐level sponsorship effects. Furthermore, while most previous sponsorship research has used convenience samples and/or fictional and/or single sponsorship contexts, the comprehensive model tested here is shown to have high external validity by its consistently good performance in predicting sponsorship effects using four real sponsorships and representative samples.

The Effects of Self-Efficacy, Motivation to Transfer, and Situational Constraints on Transfer Intentions and Transfer of Training

An important dimension of training effectiveness relates to how well skills learned during training are transferred to the workplace. The current study examines the effects of several individual characteristics (Self-efficacy, Motivation to Transfer, Training Reactions, Goals for Transfer and Commitment to Transfer Goal) and Situational Constraints on perceived Transfer Success. LISREL VII (Joreskog & Sorbom, 1989) was used to determine the fit of a mediated effects model of how the variables would affect transfer success. Self-efficacy and Motivation to Transfer were found to be significantly related to transfer intentions (Goal for Transfer and Commitment to Transfer Goal) while Goal for Transfer and Commmitment to Transfer Goal were positively related to Transfer Success. The implications of these results for maximizing the transfer of training are discussed.

Body size and perceptions of coaching behaviors by adolescent female athletes

Abstract Objectives To investigate relations among body size, perceptions of coaching behaviors, and attitudes toward the coach and sport in adolescent female athletes in three sports. Design Field correlational design. Method Female athletes, 14–18 years, participating in high school basketball, gymnastics, and soccer ( N =227) completed questionnaires dealing with the perceived frequency of coaching behaviors, evaluative reactions to the coach, and liking for the sport. Coaches rated the ability and performance of each athlete during the season. Results Partial correlations between indicators of body size and athlete perceptions of coaching behaviors, controlling for age and ratings of ability and performance, varied by sport. Among gymnasts, measures of body size were associated with less positive and supportive interactions with coaches and less liking for the coach. Contrary to expectations, the stature of the basketball players was unrelated to their perceptions of coaching behaviors or their liking for the coach and sport. Body size was unrelated to athlete perceptions of coaching behaviors and evaluative responses in soccer. Conclusions In support of [Petersen, A. C., & Taylor, B. (1980). The biological approach to adolescence: Biological change and psychological adaptation. In J. Adelson (Ed.), Handbook of adolescent psychology (pp. 117–155). New York: Wiley–Interscience.] Mediated Effects Model of Psychological Adaptation to Puberty, the results suggest that body size, even with age, ability and performance held constant, may engage sport specific stereotypes that influence coaches' positive and negative behaviors, particularly in sports where body size is related to athletic potential.

The Influence of Pioneer Status and Experience Order on Consumer Brand Preference: A Mediated-Effects Model

Within the behavioral literature, two basic explanations of the pioneering advantage have been offered. Early work focused on order-based explanations. More recently, schema-based explanations have also been suggested. The authors propose a mediated-effects model of the pioneering advantage and test the model in two separate longitudinal studies. Both experiments support the proposed model. The authors find that experience order and pioneerstatus have additive effects on brand preference such that perceptions of first-in-market and first-experienced brands are more favorable, suggesting that both explana tions are operative. The authors also provide evidence that the effects of pioneer status on brand preference are medi ated by attitude toward the brand and company credibility, while the effects of experience order on brand preference are mediated by attitude toward the brand and attribute re call. These data support the notion that the effect of pio neer status on brand preference is the result of both brandlevel and company-level associations.

Identity Style and Well-Being: Does Commitment Matter?

A case is made for the role that identity processing styles and identity commitment may play in personal well-being. I argue that research on identity commitment is of interest in its own right and it may also serve to clarify some of the relationships found between identity processing styles and outcome variables. Results from 2 studies are used to illustrate 3 ways in which commitment and processing styles may combine to influence outcome variables: a direct-effects model, a mediated-effects model, and a moderated-effects model. Speculations are advanced regarding different types of identity commitments and the functions they may serve in enhancing well-being and everyday functioning.

Relation of Social Support and Self-Esteem to Problem Behavior:

Relations of social support and self-esteem to problem behavior were investigated among 347 young adolescents. Using structural equation modeling, three models were evaluated: a mediational model in which social support is related indirectly to problem behavior via intervening effects on self-esteem, a mediated and direct effects model in which social support has a direct relation to problem behavior in addition to an indirect linkage via self-esteem, and a direct effects model in which the relation of social support to problem behavior is not mediated by self-esteem because of the lack of an independent effect of esteem on problem behavior. The best fitting model was the mediated and direct effects model. In general, social support and self-esteem predicted less involvement in problem behavior. However, after taking into account variance shared with a general self-esteem construct, unique variance in peer self-esteem predicted greater problem behavior.

Components of Type A behavior pattern and occupational stressor-strain relationship: testing different models in a sample of industrial managers.

The authors analyzed empirically the roles of impatience-irritability and ambition-energy components of the Type A behavior pattern (TABP) in the occupational stressor-strain relationship. They tested three models, using a sample of 659 industrial managers to determine whether the TABP components affected strain independently from perceived stressors (the direct effects model); or indirectly, by moderating effects of perceived stressors (the moderated effects model); or whether perceived stressors provoked TABP components, which influenced the number of strain symptoms (the mediated effects model). Multiple regression procedures showed, as expected, that the two TABP components acted quite differently in the stress process. With the direct effects model, the impatience-irritability component consistently increased numbers of psychological and physiological symptoms, regardless of perceived occupational stressors. The ambition-energy component, on the other hand, was activated by an abundance of development possibilities experienced at work. This, in turn, partly explained the decrease in perceived levels of psychological and physiological symptoms. The results relating to the ambition-energy component supported the mediated effects model and demonstrated a positive effect on subjective health perceptions.

Socioeconomic Disadvantage, Proximal Environmental Experiences, and Socioemotional and Academic Adjustment in Early Adolescence: Investigation of a Mediated Effects Model

Socioeconomic Disadvantage, Proximal Environmental Experiences, and Socioemotional and Academic Adjustment in Early Adolescence: Investigation of a Mediated Effects Model

Socioeconomic Disadvantage, Proximal Environmental Experiences, and Socioemotional and Academic Adjustment in Early Adolescence: Investigation of a Mediated Effects Model

This study investigated interrelations among conditions of household socioeconomic disadvantage, proximal environmental experiences, and adaptational outcomes in a sample of 398 middle grade, early adolescents from a predominantly poor, rural area. Findings indicated that levels of disadvantage were related to both socioemotional and academic adjustment, with those from relatively disadvantaged backgrounds faring most poorly. Specifically, youth from homes in which adults were employed in low-income, unskilled occupations were found to have lower levels of school performance and achievement compared to those from homes in which adults were employed in higher paying semi-skilled or skilled/professional occupations. Further, youth from families in which neither parent had graduated from high school exhibited significantly worse socioemotional and academic adjustment than did those whose parents had higher educational levels. Youth who lived in relatively disadvantaged homes also reported more negative experiences of proximal environmental conditions relating to family and school contexts and greater exposure to stressful life events. Most notably, findings provided support for employing an ecological-mediational perspective to understand patterns of linkage between socioeconomic disadvantage and levels of adjustment. Support for this viewpoint included the finding that proximal environmental experiences were significant predictors of adolescent adjustment, independent of shared variance with conditions of household disadvantage, whereas conditions of disadvantage in several instances were no longer related significantly to indices of adjustment once their association with proximal environmental conditions was taken into account. The discussion considers implications for the targeting and scope of ecologically oriented approaches to preventive intervention.