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871.
In this paper, we propose a theoretical framework for designing on-line situated assessment tools for multimedia instructional systems. Based on an ecological psychology approach to situated learning, a graph theoretic methodology is applied to monitor students' performance (solution paths) throughout the learning activity. Deviation of the student's path from the target (expert) path generates indicators which can function as alerts to the student and to the instructor. The information collected in the dribble files and presented visually enables the instructor to identify problems quickly and intervene appropriately. The feasibility of the methodology is explored in case studies describing three instructional systems that teach (1) critical thinking and problem-solving skills, (2) principles of hemodynamic monitoring and treatment, and (3) orthodontic treatment, respectively.  相似文献   
872.
873.
Three experiments investigated conditioning of the rabbit’s nictitating membrane response (NMR) in a second-order conditioning procedure which intermixed first-order trials (CS1-US) and second-order trials (CS2-CS1) from the outset of training. Experiment 1 provided a controlled demonstration that substantial levels of second-order conditioning can be obtained with the NMR preparation. Experiment 2 showed that the level of CR acquisition to CS2 was an inverse function of the CS2-CS1 interval over the values of 400, 800, and 2,400 msec. Experiment 3 found that CR acquisition to CS2 and CS1 in second-order conditioning varied in a parallel fashion across CS1-US intervals. Similarly, Experiment 3A found that the level of CR acquisition to the two components of a serial compound (CSA-CSB-US) varied in a parallel fashion as a function of the CSB-US interval. The results of the CS2-CS1 and CS1-US interval manipulations were all predictable from the known CS-US interval effects in NMR conditioning with a single CS. The present results are discussed with regard to their implications for accounts of serial compound conditioning and second-order conditioning.  相似文献   
874.
This paper considers whether student motivation might be impacted by the replacement of a straight (A, B, C, D, F) grading system with a plus/minus system (A, A?, B+ … D?, F). The data that are examined are from several undergraduate economics classes at a mid‐sized midwestern university in the United States. The data includes student characteristics, student performance and students’ choices of either a plus/minus or a straight grading system. In this admittedly small‐scale study students, who chose plus/minus grading, were not significantly more motivated than students who opted for straight grading.  相似文献   
875.
OBJECTIVE: Assessing the risk of further offending behavior by adult sexual perpetrators of children is highly relevant and important to professionals involved in child protection. Recent progress in assessing risk in sexual offenders has established the validity of actuarial measures, although there continues to be some debate about the application of these instruments. This paper summarizes the debate between clinical and actuarial approaches and reviews the "base rate" for United Kingdom sexual offense reconviction. METHOD: A review of the literature revealed 16 UK sexual reconviction studies, 8 using incarcerated samples (N=5,915) and 8 using non-incarcerated samples (N=1,274). UK estimates of sexual reconviction rates are compared with European and North American studies. RESULTS: The mean sexual reconviction rates for the incarcerated sample at 2 years (6.0%), 4 years (7.8%) and 6 years or more (19.5%) were higher than that of the comparative non-incarcerated sample at 2 years (5.7%), up to 4 years (5.9%), and 6 years or more (15.5%). The overall sexual reconviction rate for both samples combined was 5.8% at 2 years, and 17.5% at 6 years or more. CONCLUSIONS: The sexual reconviction rate for incarcerated sexual offenders is higher than that of non-incarcerated sexual offenders. The UK sexual reconviction rates were comparable with European and North American studies.  相似文献   
876.
The relation is studied between teachers’ pedagogical content knowledge of reading and the quality of their subsequent classroom behaviour in teaching fluent reading. A confirmatory factor analysis model with two latent variables is tested and shows adequate goodness-of-fit indices. Contrary to our expectations, the results of structural equation modelling reveal a small but significant γ-value of .29, indicating that only 8% of the variance in teachers’ classroom behaviour in teaching fluent reading is accounted for by teachers’ pedagogical content knowledge of reading. Presumably teacher knowledge is not as stable and conclusive as one might think. More research is needed in determining the factors that work restricting for teachers in putting their knowledge into classroom practice. It is recommended that preservice and in-service teacher training should not be limited to transfer of knowledge, but should also assist teachers in designing and performing effective fluent reading instruction.  相似文献   
877.
To increase the teacher efficacy of student teachers, they need positive classroom experiences: mastery experiences. These mastery experiences have to be created by the student teachers themselves. Therefore, student teachers need a tool to better understand problematic teaching experiences and help them create positive classroom experiences. Nine student biology teachers used this attribution support tool when reflecting on multiple lessons taught in classes they considered difficult. They scored their lessons and filled in a teacher efficacy questionnaire after each lesson. The results show that teacher efficacy increased and the number of failures during the lessons decreased; on average, the self-awarded marks per teacher per lesson increased, indicating an increase in mastery experiences. Therefore, the attribution tool seems to be a promising tool for student teachers to enhance their teacher efficacy and to support reflection on problematic teaching experiences.  相似文献   
878.
Two conventional scores and a weighted score on a group test of general intelligence were compared for reliability and predictive validity. One conventional score consisted of the number of correct answers an examinee gave in responding to 69 multiple-choice questions; the other was the formula score obtained by subtracting from the number of correct answers a fraction of the number of wrong answers. A weighted score was obtained by assigning weights to all the response alternatives of all the questions and adding the weights associated with the responses, both correct and incorrect, made by the examinee. The weights were derived from degree-of-correctness judgments of the set of response alternatives to each question. Reliability was estimated using a split-half procedure; predictive validity was estimated from the correlation between test scores and mean school achievement. Both conventional scores were found to be significantly less reliable but significantly more valid than the weighted scores. (The formula scores were neither significantly less reliable nor significantly more valid than number-correct scores.)  相似文献   
879.
This paper focuses on a pattern design method for a 3D triangular garment surface. Firstly, some definitions of 3D style lines are proposed for designing the boundaries of patterns as drawing straight lines or splines on the triangular surface. Additionally some commonly used style lines are automatically generated to enhance design efficiency. Secondly, after style lines are preprocessed, a searching method is presented for quickly obtaining the boundaries and patches of a pattern on the 3D trian- gular surface. Finally a new pattern design reuse method is introduced by encoding/decoding the style line information. After style lines are encoded, the pattern design information can be saved in a pattern template and when decoding this template on a new garment surface, it automates the pattern generation for made-to-measure apparel products.  相似文献   
880.
The paper proposes a new method for computation of the Wigner-Ville distribution (WVD) taking account of the conjugate symmetry of the WVD kernel function and the periodicity and symmetry of the trigonometric function. The method transfers the computation of WVD into real field from complex field to remove the redundancies in the fast Fourier transform(FFT) computation. The realization of fast cosine operation and fast sine operation considerably reduces the computation cost. Theoretical analysis shows that  相似文献   
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