A photographic impact testing machine for measuring the varying intensity of an impulsive force     

B.W. Dunn 《Journal of The Franklin Institute》1898,145(1):36-47

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Individual Differences in the Stability and Change of Childhood Depression: A Growth Mixture Model With Structured Residuals     

Matt Hawrilenko  Katherine E. Masyn  Janine Cerutti  Erin C. Dunn 《Child development》2021,92(4):e343-e363

Studies of developmental trajectories of depression are important for understanding depression etiology. Existing studies have been limited by short time frames and no studies have explored a key factor: differential patterns of responding to life events. This article introduces a novel analytic technique, growth mixture modeling with structured residuals, to examine the course of youth depression in a large, prospective cohort (N = 11,641, ages 4–16.5, 96% White). Age-specific critical points were identified at ages 8 and 13 where depression symptoms spiked for a minority of children. Most depression risk was due to dynamic responses to environmental events, drawn not from a small pool of persistently depressed children, but a larger pool of children who varied across higher and lower symptom levels.  相似文献   

Assessment of mathematics and reading performance: An examination of the correspondence between direct assessment of student performance and teacher report     

Tanya L. Eckert  Erin K. Dunn  Robin S. Codding  John C. Begeny  Ava E. Kleinmann 《Psychology in the schools》2006,43(3):247-265

Teacher judgments have been identified as a primary source of information regarding student academic achievement. Research examining the accuracy of teachers' judgments in assessing students' academic abilities has shown relatively high accuracy. However, previous studies have relied primarily on norm‐referenced measures to obtain estimates of students' achievement in reading and mathematics. Recent developments in the assessment of students' academic skills, such as Curriculum‐Based Measurement (CBM), provide a direct estimate of students' skill levels in basic areas such as reading and mathematics. The purpose of the present study was to examine the extent to which teachers' perceptions of students' reading and mathematics skills corresponded to direct estimates of students' reading and mathematics skills. Two second‐grade teachers estimated the reading and mathematics skills of 33 second‐grade students. Results of this study indicated that teachers were not accurate in assessing their students' mathematics functioning. Teachers were more accurate in assessing the occurrence of Mastery mathematics levels in basic addition, but were very inaccurate in assessing the occurrence of Mastery, Instructional, or Frustrational mathematics levels in all other skills assessed. In reading, teachers' judgment accuracy varied as a function of grade‐level material and instructional level. Specifically, teachers experienced considerable difficulty accurately identifying students who were reading at a Mastery level in grade‐level or above‐grade‐level material. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 247–265, 2006.  相似文献   

Australian academics and transnational teaching: an exploratory study of their preparedness and experiences     

Lee Dunn 《高等教育研究与发展》2006,25(4):357-369

Australia is now the third largest provider of education to overseas students. Between 1994 and 2000 the number of overseas students taught by Australian universities increased by 150% to 107,622. It is estimated that 41% of the recent growth in international education has been in offshore enrolments, with each of Australia’s 38 universities now providing offshore education. This paper reviews recent Australian literature on transnational teaching and presents an overview of a study with academics who teach transnationally and who are drawn from nine Australian universities. The study covers the professional development and teaching experiences of these academics and their perceptions of the induction/orientation and ongoing professional development needed to support the delivery of quality trans‐cultural education offshore.  相似文献   

Determinants of pigeons’ choice between certain and probabilistic outcomes     

Marcia L. Spetch  Michael V. Mondloch  Terry W. Belke  Roger Dunn 《Learning & behavior》1994,22(3):239-251

Pigeons chose between 50% and 100% reinforcement on a discrete-trials concurrent-chains procedure with fixed-ratio 1 initial links and fixed-time terminal links. The 100% alternative always provided food after a terminal-link delay, whereas the 50% alternative provided food or blackout equally often after a delay. Additionally, the terminal-link stimuli on the 50% alternative were correlated with the outcomes in signaled, but not in unsignaled, conditions. The effects of intertrial-interval duration and length of the terminal-link delays on choice of the 50% alternative were investigated in four experiments. Preference for the 50% alternative varied with signal condition and duration of the terminal link leading to food, but not with duration of either intertrial interval or the terminal link leading to a blackout. The results are discussed in terms of conditioned-reinforcement effects, Mazur’s hyperbolic-decay model, and delay reduction. This research was supported by a Natural Sciences and Engineering Research Council of Canada research grant awarded to the first author.  相似文献   

Perspectives on the Contribution of Social Science to Adapted Physical Activity: Looking Forward,Looking Back     

Janice Causgrove Dunn  John Cairney  Chantelle Zimmer 《Quest (Human Kinetics)》2016,68(1):15-28

ABSTRACT

In this article, we reflect on the contributions of the social sciences to the field of adapted physical activity by examining the theories and methods that have been adopted from the social science disciplines. To broaden our perspective on adapted physical activity and provide new avenues for theoretical and empirical exploration, we discuss and evaluate broad ideas/tensions arising from the social science literature—the individual versus social/ecological, and social science of adapted physical activity versus social science in adapted physical activity. We intentionally focus discussion on the application of specific lines of inquiry in the social sciences that have not yet emerged (or have done so only in limited applications) in the field of adapted physical activity. Such untapped areas of scholarship in the social sciences can lead to broader understanding, innovations, and new lines of inquiry when applied to an adapted physical activity context.  相似文献   

Influence of motherhood on the implicit academic self-concept of female college students: Distinct effects of subtle exposure to cues and directed thinking     

Thierry Devos  Erin Viera  Priscila Diaz  Roger Dunn 《European Journal of Psychology of Education - EJPE》2007,22(3):371-386

Despite notable steps toward gender equality and significant changes in gender roles, women continue to face tension between academic aspirations and the more traditional role of caregiver. The goal of the present research was to examine how this conflict might be revealed through assessments of associations that cannot be consciously controlled. In two experiments, college women completed implicit association tasks measuring the strength of their academic identification. Experiment 1 (N=55) showed that implicit academic identification was weaker when motherhood cues were present (rather than absent). In Experiment 2 (N=73), implicit academic identification was weaker when participants reflected on their aspirations to become a college graduate rather than aspirations to be a mother. These findings emphasize the malleability of the implicit academic self-concept. More precisely, they document that subtle exposure to cues and more deliberate thought processes produce distinct effects. This research contributes to a better understanding of contextual influences on the academic self-concept of college women and their potential implications for academic performances.  相似文献   

A Multi-Method Multi-Analytic Approach to Establishing Internal Construct Validity Evidence: The Sport Multidimensional Perfectionism Scale 2     

John K. Gotwals  John G. H. Dunn 《Measurement in physical education and exercise science》2013,17(2):71-92

The purpose of the study was to examine the norm-referenced and criterion-referenced reliability and validity of the Back-Saver Sit-and-Reach Test (BSR; Single-Leg Sit-and-Reach; Cooper Institute for Aerobics Research [CIAR], 1999). One hundred seventy-nine elementary school children (87 boys and 92 girls), 6-12 years old participated, with 44 randomly selected participants retested on a second day. The BSR, Modified Schober (MSCH, Low Back Criterion Test), Passive Straight Leg Raise (PSLR, Hamstring Criterion Test), Active Knee Extension, True Lumbar Extension, True Lumbar Flexion, and Double-Leg Sit-And-Reach were administered in random order. Intraclass correlation coefficients (norm-referenced reliability) for the BSR were extremely high (.98-.99) for both boys and girls. Pa and Km (criterion-referenced test-retest reliability) for the right leg was .90 and .80, respectively, for boys; and .91 and .82 for girls, indicating the participants were classified consistently across days. Norm-referenced validity coefficients (Pearson product-moment correlations, r) of the BSR as a measure of hamstring flexibility were moderate for boys (.67 and .68, right and left legs, respectively) and moderately low for girls (.47 and .44, right and left legs). Correlation coefficients of the BSR as a measure of low back flexibility were extremely poor for boys and girls, with coefficients ranging from .003 to .06. Criterion-referenced validity of BSR for hamstring flexibility was low and unacceptable for right and left legs (Km: .48, .58, respectively), for both boys and girls (Km: .40, .22). The BSR appears to be similar to the Double-Leg Sit-and-Reach in that it is a test of hamstring flexibility but not low back. The criterion-referenced standards for both BSR and PSLR should be re-examined and adjusted to provide a better degree of classification agreement between the BSR and the criterion measure (PSLR).  相似文献   

Gymnastics     

Yoshiaki Takei  J. Hubert Dunn  Erik Blucker 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(2):141-162

The 16 highest‐scored Roche vaults (G1) performed during the 2000 Olympic Games were compared with those receiving the 16 lowest‐scores (G2). A 16‐mm motion picture camera operating at 100 Hz recorded the vaults during the competition. The results of t tests (p < .05) indicated G1, compared to G2, had (a) shorter time of board support, greater normalised average upward vertical force and backward horizontal force exerted by the board, greater change in the vertical velocity while on the board, and greater vertical velocity at board take‐off, (b) comparable linear and angular motions in pre‐flight, (c) smaller backward horizontal impulse exerted by the horse, smaller loss of the horizontal velocity while on the horse, and greater horizontal and vertical velocities at horse take‐off, (d) greater height and larger horizontal distance of post‐flight, (e) higher body mass centre at knee release, and (f) higher mass centre, greater normalised moment of inertia, and smaller vertical velocity at mat touchdown. Therefore, gymnasts and coaches should focus on sprinting the approach; blocking and pushing‐off the take‐off board rapidly and vigorously; departing the board with a large vertical velocity; exerting large downward vertical force and small forward horizontal force from the handstand position while on the horse; departing the horse with large horizontal and vertical velocities; and completing the majority of the double salto forward near the peak of trajectory and releasing the knees above the top of the horse to prepare for a controlled landing.  相似文献   

TELEVISION AND THE EDUCATION OF THE YOUNG     

Gwen Dunn 《Learning, Media and Technology》1980,6(2):47-52

This paper, from the 1979 Conference, ‘Television In Society’ begins by defining the educational process as one of persisting, despite initial failures, to acquire understanding or mastery, and underlining the uniqueness of each individual learner. The author reports on the results of a one‐year study of the viewing habits of pre‐school children. Little ‘rising fives’ are such heavy viewers that they must feel a sense of loss when school attendance deprives them of ‘their’ television, perhaps the most valuable ‘child‐minder’ of all. Television delights these veteran under‐five viewers and provides an aid that parents and teachers can welcome; it also seems to stimulate little or no ‘participation’ and to inhibit language skills. Older children are also voracious viewers, but the author's experience suggests that television does not of itself inhibit reading and that to blame violent behaviour on viewing of violence is humbug. In conclusion it is suggested that educators are as yet failing to recognize the paramount importance of television in children's lives: there is an urgent need for education to acknowledge this in its curricula and for children (and adults) to find out more about how television is created. The Educational Television Association could play an important role here.  相似文献