Perception of kinematic characteristics of tennis strokes for anticipating stroke type and direction     

Shim J  Les Carlton G  Kwon YH 《Research quarterly for exercise and sport》2006,77(3):326-339

The purpose of this study was to determine the sources of visual information used by highly skilled tennis players in anticipating their opponent's shots. In Experiment 1, motion analysis of the strokes showed that the relative motion between the racquet and forearm was different between the ground strokes and lobs, but there were no reliable kinematic differences when shot direction was varied. In Experiment 2, 12 skilled tennis players observed the opponent hitting strokes in a normal video or in a point-light display with different segments occluded. Players' anticipation accuracy was not degraded by the use of the point-light display. Occluding the racquet and forearm significantly reduced the participant's ability to determine the type of stroke produced.  相似文献   

Against the current: A grounded theory study on the estrangement experiences of a select group of Filipino gay older persons     

Allan B. de Guzman  Les Paul Valdez  Maverick B. Orpiana  Nikki Angela F. Orantia  Patrick Van E. Oledan  Karla Monica Cenido 《Educational gerontology》2017,43(7):329-340

According to Healthy People (2011), in order to understand the health concerns of the Lesbian, Gay, Bisexual, and Transgender (LGBT), the oppression and discrimination that they have faced must be scrutinized. Among the many issues they face, their estrangement experiences are one of the most understudied. However, little is known about how it is experienced by the gay elderly population, hence, this investigation. This grounded theory purports to describe the process by which estrangement is experienced among the Filipino gay older adults. Strauss and Corbin’s Grounded Theory (1990) design was utilized. A total of 10 gay older persons were purposively chosen to participate in semi-structured interviews. Field texts were subjected to thematic analysis involving open, axial, and selective coding. The study generated The Sailing Model of Estrangement. Remarkably, three phases relative to estrangement emerged, namely: sequestering, striving, and surviving. Primarily, the sequestering phase involves the gay persons’ need to express self, search for acceptance, and its subsequent reactions. The striving phase typifies the struggle in dealing with estrangement leading to either feelings of depression, remorse and shame or positivity, hopefulness, and motivation. Finally, in the surviving phase, gay persons may either feel contented and fulfilled or sad, lonely, and remorseful as they acquiesce aging with estrangement. Findings of the study offer an understanding of how Filipino gay older adults employ coping strategies in response to estrangement.  相似文献   

Investigative interviews of alleged sexual abuse victims with and without anatomical dolls     

Michael E. Lamb  Irit Hershkowitz  Kathleen J. Sternberg  Barbara Boat  Mark D. Everson 《Child abuse & neglect》1996,20(12):1251-1259

Verbal and nonverbal responses by alleged victims of child sexual abuse were coded for length, amount of information, and the manner in which they were elicited by the interviewer. In 16 of the interviews, anatomical dolls were employed for the purposes of demonstration, whereas they were not used in another eight cases matched with respect to other characteristics of the children and the alleged events. Children interviewed with dolls provided an equivalent number of details and spoke as many words in the substantive portion of the interview as did children interviewed without dolls, and interviewers in the two groups used similar probes to elicit information. However, the average responses by the children were significantly longer and more detailed when dolls were not used. Children gave longer and more detailed responses to open-ended invitations when dolls were not used. Caution is necessary when interpreting these findings.  相似文献   

Identifying and developing creative giftedness     

Robert J. Sternberg 《Roeper Review》2013,35(2):60-64

To a large extent, creativity is a decision. Children as well as adults are creative, not by virtue of an innate ability, but by virtue of a set of decisions. In essence, they decide for creativity, rather than an innate set of abilities deciding whether they are creative. Thus, creative giftedness is not a fixed trait, but a decision‐making skill that can be developed. In this article, I present ten decisions people can make to decide for creativity. Included are teaching examples of these decisions as well as teaching activities to facilitate students' learning how to make these decisions.  相似文献   

The development of pattern recognition ability in children     

Les Sternberg  Paul Larson 《Contemporary educational psychology》1976,1(2):146-156

Pattern recognition development was studied in high and low ability preschool, kindergarten, and first-grade youngsters. Pattern recognition was assessed by the administration of 96 pattern tasks which measured the ability of a youngster to find: (a) duplicate patterns and elements to a model; (b) the opposite pattern to a model; and (c) duplicate patterns but different elements than in the model. Aside from main effects for grade level, ability level, and pattern task, a significant three-way interaction was noted. This interaction was analyzed in terms of its component simple effects. The implication of these simple interaction effects for Piagetian theory and educational practice were discussed.  相似文献   

Comparing the pre- and post-impact ball and racquet kinematics of elite tennis players' first and second serves: a preliminary study   总被引：1，自引：0，他引：1  

Chow JW  Carlton LG  Lim YT  Chae WS  Shim JH  Kuenster AF  Kokubun K 《Journal of sports sciences》2003,21(7):529-537

The aim of this study was to compare the pre- and post-impact three-dimensional kinematics of the ball and racquet during first and second serves performed by elite tennis players. Data were collected from four male and four female right-handed professional players during competition using two high-speed cameras (200 Hz). For each player, one first serve and one second serve from the 'deuce' or right service court that landed within the specified target area were analysed. To test for significant differences between the first and second serves, Wilcoxon tests (P < or = 0.05) were performed on selected parameters. The results indicate that the ball travelled forward and to the left during the flight phase of the toss in all but one trial. The average pre-impact ball forward location for the first serve was significantly more in front and had a higher associated forward ball velocity than the corresponding values for the second serve. On average, the decrease in post-impact ball speed from the first to the second serve was 24.1%. No significant differences between the first and second serves were found in the pre-impact racquet head speed and orientation, which was represented as a unit vector perpendicular to the racquet face. The major adjustments made by the players when going from the first to second serve were a decrease in pre-impact ball forward location (P < or = 0.01) and an increase in the pre-impact racquet vertical and lateral velocities (both P < or = 0.05). This implies that the players tossed the ball closer to the body and imparted topspin and sidespin on the ball by changing the racquet vertical and lateral velocities when going from the first to the second serve.  相似文献   

The Future of Intelligence Testing     

Robert J. Sternberg 《Educational Measurement》1986,5(3):19-22

Though the most widely used "intelligence" tests have changed little in the last half century, Dr. Stern-berg predicts a variety of new influences of future intelligence testing, ranging from the ways we conceptualize intelligence, to the manner in which we pose problems to assess it.  相似文献   

Endurance training adherence in elite junior netball athletes: a test of the theory of planned behaviour and a revised theory of planned behaviour     

Palmer CL  Burwitz L  Dyer AN  Spray CM 《Journal of sports sciences》2005,23(3):277-288

This study examined the utility of Ajzen's (1985) theory of planned behaviour and Maddux's (1993) revised theory of planned behaviour to predict endurance training intentions and adherence of elite junior netball athletes. One hundred and fifteen athletes from the England Netball World Class Start Programme were assessed on constructs central to the predictions of the two theories. Adherence to a recommended endurance training programme was recorded in self-report diaries across a 9-week period. Validity for the diaries was supported by significant correlations (P < 0.001) with recalls across 7 days and 9 weeks. Adherence was moderate and variable between athletes (mean = 66.05, s = 25.75%). Two separate path analyses were conducted to examine the predictions of the theories. Goodness-of-fit indices suggested acceptable fit of the data to the models. Analyses showed that attitude towards the new behaviour, subjective norms and perceived behavioural control predicted training intentions. The relationship between intention and adherence was weak. The present results suggest that the constructs of the theory of planned behaviour offer some insight into the explanation of intentions to follow an endurance training programme. Constructs unique to the revised theory of planned behaviour did not significantly predict training intentions or behaviour. Implications for practitioners working with team sport performers are provided.  相似文献   

Effects of early and later family violence on children's behavior problems and depression: a longitudinal, multi-informant perspective     

Sternberg KJ  Lamb ME  Guterman E  Abbott CB 《Child abuse & neglect》2006,30(3):283-306

OBJECTIVES: To examine the effects of different forms of family violence at two developmental stages by assessing a sample of 110 Israeli children, drawn from the case files of Israeli family service agencies, studied longitudinally in both middle childhood and adolescence. METHODS: Information about the children's adjustment was obtained from parents, teachers, and the children themselves when the children averaged 10.6 and 15.9 years of age using the Child Behavior Checklist (CBCL), Teacher Report Form (TRF), Youth Self-Report (YSR), and Children's Depression Inventory (CDI). Information about the history of family violence was obtained from the mothers, fathers, children, and social workers. RESULTS: The results paint a mixed picture of the effects of family violence on children and adolescents. The relationship between concurrent behavior problems and abuse group varied by informant and study phase, although they were strongest when children were the informants. Predictions regarding the relationship between early abuse and later adjustment were only partially confirmed. Different informants did not agree about which groups of children were most adversely affected, there was little stability over time in the pattern of reported effects, and children were more likely than other informants to report levels of maladjustment that varied depending on recent or concurrent exposure to family violence. Many families changed their abuse status over time, and children who were new victims at follow-up had the most internalizing problems. Girls were found to be at more risk for internalizing and externalizing behavior problems than boys. CONCLUSIONS: Multiple informants are necessary to evaluate and assess the effects of family violence on children's behavior. Younger children may be more susceptible to the effects of family violence than older children, but problems manifest by some children may not carry over to adolescence. Changes in family and parenting practices, as well as in children's capacity to appraise and cope with family violence may help mitigate the adverse effects of family violence.  相似文献   

From Symphony to Jazz: The concept of strategy in education     

Les Bell 《School Leadership & Management》2013,33(4):449-460

This paper considers the derivation of the concept of strategy and its deployment as a management technique to enable organisations to prepare for the future. It then examines the related growth of school development planning and explores the extent to which this can be considered to be strategic. It is then argued that whether or not school development planning is strategic, the use of strategy in organisations is no longer either possible, if it ever was, or appropriate. The paper concludes by proposing an alternative basis for planning derived from a combination of marginal incrementalism and feminist literature on problem solving.  相似文献