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991.
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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   
994.
Commonly used technical anatomy and physiology (A&P) terms are predominantly rooted in Latin and Greek vocabulary, so it is commonly inferred that a solid grounding in Latin and Greek roots of medical terminology will improve student learning in anatomy and related disciplines. This study examines the association of etymological knowledge of A&P terms and A&P course performance among 446 undergraduates in their first semester of the study of human gross anatomy and physiology, with a more detailed analysis of the characteristics of 52 students who filled out surveys about their prior knowledge and experiences related to medicine or anatomy. In both data sets, there was only a weak positive correlation between the performance on a quiz of Latin and Greek medical terms and the students' performance on regular assignments. The presumption that familiarity with Latin and Greek word roots has a strong influence on successful learning of anatomy is not supported by these data. Future research should address whether or not there are particular skills associated with using etymological knowledge in improving A&P course performance.  相似文献   
995.
996.
Providing for equality of educational opportunity at racially isolated schools continues to be an important area of concern for educational policy makers. Quality teachers to staff instruction programs at these schools is essential to promoting equal opportunity for minority groups. Unfortunately, these schools continue to suffer chronic teacher shortages. Recently, California implemented a teacher certification examination (CBEST) designed specifically to improve the quality of teachers entering the profession. An unintended consequence of the certification movement was the exacerbation of the teacher shortage problem at racially isolated schools. The purpose of this study is to examine the characteristics of teachers who passed and failed the CBEST. The study finds that failure rates are highest among minority teachers that are presently employed. The study also finds that the mathematics knowledge subscale scores best discriminate those passing from those failing the CBEST. An analytical approach for determining optimal cutoff scores on the CBEST which balances the need for certification with the problem of teacher shortage is proposed.  相似文献   
997.
998.
Using an updated version of the Aging Semantic Differential, 534 younger, middle age, and older participants from a college community rated female and male targets categorized as ages 21–34 and 75–85. Participants also provided views about their own aging. Repeated measures of analysis of variance examined attitudinal differences by age and gender of targets, and by participant age and gender. Female targets were viewed more positively than males by most rater groups. Older targets were viewed more positively by older participants than by other age groups. Older participants had more positive views about their own aging than did participants of younger or middle ages.  相似文献   
999.
The World Wide Web is a popular “tool” for companies. It can be used as a method of communication between companies and their customers; it also allows organizations to setup virtual storefronts that can be accessed by customers from all over the world. The ability to understand customers’ behavior is extremely important as companies strive to increase the usability and profitability of their web service. The concept of a session is a popular unit of measurement used to analyze recorded information. However, this concept is currently rather abstract and lacks definition. How we measure a session is a fundamental question for web services utilizing this concept. Currently, this question has no real answer. This paper presents a session timeout threshold model based on empirical observations as an initial answer to this question. The model seeks to provide accurate session data with respect to individual web services.  相似文献   
1000.
Invention and Productive Failure activities ask students to generate methods that capture the important properties of some given data (e.g., uncertainty) before being taught the expert solution. Invention and Productive Failure activities are a class of scientific inquiry activities in that students create, implement, and evaluate mathematical models based on data. Yet, lacking sufficient inquiry skills, students often do not actualize the full potential of these activities. We identified key invention strategies in which students often fail to engage: exploratory analysis, peer interaction, self-explanation, and evaluation. A classroom study with 134 students evaluated the effect of supporting these skills on the quality and outcomes of the invention process. Students in the Unguided Invention condition received conventional Invention Activities; students in the Guided Invention condition received complementary metacognitive scaffolding. Students were asked to invent methods for calculating uncertainties in best-fitting lines. Guided Invention students invented methods that included more conceptual features and ranked the given datasets more accurately, although the quality of their mathematical expressions was not improved. At the process level, Guided Invention students revised their methods more frequently and had more and better instances of unprompted self-explanations even on components of the activity that were not supported by the metacognitive scaffolding. Classroom observations are used to demonstrate the effect of the scaffolding on students’ learning behaviours. These results suggest that process guidance in the form of metacognitive scaffolding augments the inherent benefits of Invention Activities and can lead to gains at both domain and inquiry levels.  相似文献   
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