Applying computerized-scoring models of written biological explanations across courses and colleges: prospects and limitations     

Ha M  Nehm RH  Urban-Lurain M  Merrill JE 《CBE life sciences education》2011,10(4):379-393

Our study explored the prospects and limitations of using machine-learning software to score introductory biology students’ written explanations of evolutionary change. We investigated three research questions: 1) Do scoring models built using student responses at one university function effectively at another university? 2) How many human-scored student responses are needed to build scoring models suitable for cross-institutional application? 3) What factors limit computer-scoring efficacy, and how can these factors be mitigated? To answer these questions, two biology experts scored a corpus of 2556 short-answer explanations (from biology majors and nonmajors) at two universities for the presence or absence of five key concepts of evolution. Human- and computer-generated scores were compared using kappa agreement statistics. We found that machine-learning software was capable in most cases of accurately evaluating the degree of scientific sophistication in undergraduate majors’ and nonmajors’ written explanations of evolutionary change. In cases in which the software did not perform at the benchmark of “near-perfect” agreement (kappa > 0.80), we located the causes of poor performance and identified a series of strategies for their mitigation. Machine-learning software holds promise as an assessment tool for use in undergraduate biology education, but like most assessment tools, it is also characterized by limitations.  相似文献   

Harnessing technology to improve formative assessment of student conceptions in STEM: forging a national network   总被引：2，自引：0，他引：2  

Haudek KC  Kaplan JJ  Knight J  Long T  Merrill J  Munn A  Nehm R  Smith M  Urban-Lurain M 《CBE life sciences education》2011,10(2):149-155

Concept inventories, consisting of multiple-choice questions designed around common student misconceptions, are designed to reveal student thinking. However, students often have complex, heterogeneous ideas about scientific concepts. Constructed-response assessments, in which students must create their own answer, may better reveal students' thinking, but are time- and resource-intensive to evaluate. This report describes the initial meeting of a National Science Foundation-funded cross-institutional collaboration of interdisciplinary science, technology, engineering, and mathematics (STEM) education researchers interested in exploring the use of automated text analysis to evaluate constructed-response assessments. Participants at the meeting shared existing work on lexical analysis and concept inventories, participated in technology demonstrations and workshops, and discussed research goals. We are seeking interested collaborators to join our research community.  相似文献   

Neuromuscular control and running economy is preserved in elite international triathletes after cycling     

Bonacci J  Saunders PU  Alexander M  Blanch P  Vicenzino B 《Sports biomechanics / International Society of Biomechanics in Sports》2011,10(1):59-71

Running is the most important discipline for Olympic triathlon success. However, cycling impairs running muscle recruitment and performance in some highly trained triathletes; though it is not known if this occurs in elite international triathletes. The purpose of this study was to investigate the effect of cycling in two different protocols on running economy and neuromuscular control in elite international triathletes. Muscle recruitment and sagittal plane joint angles of the left lower extremity and running economy were compared between control (no preceding cycle) and transition (preceded by cycling) runs for two different cycle protocols (20-minute low-intensity and 50-minute high-intensity cycles) in seven elite international triathletes. Muscle recruitment and joint angles were not different between control and transition runs for either cycle protocols. Running economy was also not different between control and transition runs for the low-intensity (62.4 +/- 4.5 vs. 62.1 +/- 4.0 ml/min/kg, p > 0.05) and high-intensity (63.4 +/- 3.5 vs. 63.3 +/- 4.3 ml/min/kg, p > 0.05) cycle protocols. The results of this study demonstrate that both low- and high-intensity cycles do not adversely influence neuromuscular control and running economy in elite international triathletes.  相似文献   

Subject-specific computer simulation model for determining elbow loading in one-handed tennis backhand groundstrokes     

King MA  Glynn JA  Mitchell SR 《Sports biomechanics / International Society of Biomechanics in Sports》2011,10(4):391-406

A subject-specific angle-driven computer model of a tennis player, combined with a forward dynamics, equipment-specific computer model of tennis ball-racket impacts, was developed to determine the effect of ball-racket impacts on loading at the elbow for one-handed backhand groundstrokes. Matching subject-specific computer simulations of a typical topspin/slice one-handed backhand groundstroke performed by an elite tennis player were done with root mean square differences between performance and matching simulations of < 0.5 degrees over a 50 ms period starting from ball impact. Simulation results suggest that for similar ball-racket impact conditions, the difference in elbow loading for a topspin and slice one-handed backhand groundstroke is relatively small. In this study, the relatively small differences in elbow loading may be due to comparable angle-time histories at the wrist and elbow joints with the major kinematic differences occurring at the shoulder. Using a subject-specific angle-driven computer model combined with a forward dynamics, equipment-specific computer model of tennis ball-racket impacts allows peak internal loading, net impulse, and shock due to ball-racket impact to be calculated which would not otherwise be possible without impractical invasive techniques. This study provides a basis for further investigation of the factors that may increase elbow loading during tennis strokes.  相似文献   

Does patenting help high-tech start-ups?     

Christian Helmers  Mark Rogers 《Research Policy》2011,40(7):1016-1027

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Systems thinking, market failure, and the development of innovation policy: The case of Australia   总被引：1，自引：0，他引：1  

Mark Dodgson  Alan HughesJohn Foster  Stan Metcalfe 《Research Policy》2011,40(9):1145-1156

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Coaching competency and satisfaction with the coach: a multi-level structural equation model     

Myers ND  Beauchamp MR  Chase MA 《Journal of sports sciences》2011,29(4):411-422

The purpose of this initial predictive validity study was to determine the ability of measures derived from the Athletes' Perceptions of Coaching Competency Scale II?-?High School Teams (APCCS II-HST) to predict satisfaction with the head coach. Specification of the statistical model was informed by the mediational model of coach-athlete interactions. The technical quality of the satisfaction measure was evaluated before testing the predictive validity of the coaching competency measures. Data were collected from athletes of seven sports. Athlete observations (N?=?748) were clustered within teams (G?=?74). Multi-group confirmatory factor analyses (CFA) provided evidence for factorial invariance of a reduced version of the satisfaction measure by athlete gender. Multi-level CFA provided evidence of model-data consistency for a reduced version of the satisfaction measure. Multi-level structural equation modelling provided evidence for the ability of latent coaching competency to positively predict latent satisfaction at both the athlete level (technique competency and motivation competency) and the team level (coaching competency) and for close model-data fit. Implications of this study include: that the APCCS II-HST should be viewed as a replacement for the Coaching Competency Scale when the intended population is appropriate; a preliminary multi-level measurement model for satisfaction with one's coach that should be considered as a potential starting point in subsequent studies; and empirical support for a key relationship proposed in the mediational model of coach-athlete interactions.  相似文献   

The long-term athlete development model: physiological evidence and application   总被引：2，自引：2，他引：0  

Ford P  De Ste Croix M  Lloyd R  Meyers R  Moosavi M  Oliver J  Till K  Williams C 《Journal of sports sciences》2011,29(4):389-402

Within the UK, the "Long Term Athlete Development" (LTAD) model has been proposed by a variety of national governing bodies to offer a first step to considering the approach to talent development. The model, which is primarily a physiological perspective, presents an advancement of understanding of developing athletic potential alongside biological growth. It focuses on training to optimize performance longitudinally, and considers sensitive developmental periods known as "windows of opportunity". However, it appears that there are a number of problems with this theoretical model that are not necessarily transparent to coaches. Principally, the model is only one-dimensional, there is a lack of empirical evidence upon which the model is based, and interpretations of the model are restricted because the data on which it is based rely on questionable assumptions and erroneous methodologies. Fundamentally, this is a generic model rather than an individualized plan for athletes. It is crucial that the LTAD model is seen as a "work in progress" and the challenge, particularly for paediatric exercise scientists, is to question, test, and revise the model. It is unlikely that this can be accomplished using classical experimental research methodology but this should not deter practitioners from acquiring valid and reliable evidence.  相似文献   

Introducing e-portfolios to pre-service teachers as tools for reflection and growth: lessons learnt     

Grace Oakley  Mark Pegrum  Shannon Johnston 《Asia-Pacific Journal of Teacher Education》2014,42(1):36-50

E-portfolios are being introduced into initial teacher education programmes internationally to help pre-service teachers build records of their learning journeys and develop into reflective practitioners; to allow them to assemble collections of evidence of their achievements against graduate standards, which can function as digital CVs; and to facilitate the seeding of personal learning networks that will support lifelong learning after graduation. Despite certain tensions between these aims, the potential benefits of e-portfolios make them an increasingly popular choice in teacher education. In this article, we discuss the introduction of Wi-Fi-based e-portfolios into a Master of Teaching programme at an Australian university. These served primarily as developmental e-portfolios, or personal learning environments (PLEs), and were designed to place particular emphasis on reflective practice. We describe how the e-portfolios were perceived and used by pre-service teachers in the first year of their implementation, and indicate the challenges and limitations encountered. Lessons learnt from the implementation are outlined and recommendations are proposed.  相似文献   

A dialogue on dialectics     

Mark Zuss 《Cultural Studies of Science Education》2014,9(3):567-573

The following comments are intended as a constructive critique of the questions posed by Lima, Osterman and Rezende. The issues raised by the authors advocate for a return in research and teaching to the impetus of dialectical materialist approaches in the originators of the sociocultural school, including Vygotsky. The focus of this response is directed toward the need to historicize dialectics itself, as a tradition, method and approach. The relation between dialectics and materialist critique requires a critical scrutiny that also provides pedagogical spaces and temporalities for an entwining of dialectical practices with dialogic interchange. The intent of the following comments is to engage with the authors in shaping a materialist critique of some of the ways through which the sociocultural school and ‘Vygotskyian inspired practices have been domesticated within the neoliberal university.  相似文献