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51.
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
52.
Some hypotheses concerning the evolution of polysemous words   总被引:1,自引:0,他引:1  
The evolution of polysemous words is examined in three studies. Study 1 indicates that older words are more polysemous than recent words, and that frequently used words are more polysemous than infrequently used words. These effects were replicated, controlling for word concreteness (Study 2) and evaluation (Study 3), using two other samples of words. If words evolve additional meanings through metaphor (MacCormac, 1985), then variables (such as concreteness and evaluation) that play a role in metaphor may mediate the evolution of polysemy. The correlation between concreteness and polysemy was negligible (Study 2). As hypothesized, evaluation is a significant predictor of polysemy: Negative words are more polysemous than positive words, and relatively neutral words are more polysemous than evaluatively extreme words. These findings are consistent with the notion that polysemous words evolve, in part, through metaphor.  相似文献   
53.
The purpose of this study was to investigate the structure of emotional responses to pictorial stimuli within the affective space defined by orthogonal dimensions of positive affect (PA) and negative affect (NA). College student participants (N = 151) viewed 60 color photographic slides from the International Affective Picture System (Lang, Bradley, & Cuthbert, 1995) and rated their emotional responses to each slide using the Positive and Negative Affect Schedule (Watson, Clark, & Tellegen, 1988). Consistent with prediction, affective reactions to pleasant slides were characterized as high in PA, and low in NA. Unpleasant slides produced elevations on the NA scale, but contrary to expectation, also produced elevated ratings of PA, with the magnitude of PA scale scores increasing systematically with NA scale scores. The results suggest an interesting divergence between the structure of pictorially elicited affective reactions and that of ad hoc mood states. Directions for future research are discussed in relation to the unique properties of the slide viewing paradigm.  相似文献   
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Several neural networks were developed inMathematica in order to explore the role of “spiky” neurons in neural network memory simulations. UsingMathematica for this task confirmed its value as a powerful tool for neural network development: It exhibited distinct advantages over other environments in programming ease, flexibility of data structures, and the graphical assessment of network performance.  相似文献   
56.
Course sequences are strands of courses in particular content areas that span a student's educational career. Courses that are differentiated and sequentially organized, such as mathematics and science course sequences, create opportunities for positional advantages in a school's curricular structure. When students make a nonroutine change of schools – that is, transferring to a school outside of the regular attendance zone – they are at risk of changing their positional advantage. Using data from the National Education Longitudinal Study of 1988–94 (NELS:88–94), we examine the educational outcomes of sequences and explore curricular dislocations within the context of school choice. We find that the strongest predictors of 12th-grade mathematics and science course sequences are a student's course sequences at 10th grade. With regard to outcomes, students in higher mathematics and science sequences show greater achievement gains. Furthermore, students in higher mathematics sequences are less likely to have behavior problems and are more likely to graduate from high school and attend college. Students who make a nonroutine change of schools are more likely to be in lower course sequences than students who do not transfer. Thus, course sequences in mathematics and science are tangible experiences with real consequences for students' lives during and beyond high school and are sensitive to transitions which disrupt the continuity of students' high school careers.  相似文献   
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Recent memory theory has emphasized the concept ofneed probability—that is, the probability that a given piece of learned information will be tested at some point in the future. It has been proposed that, in real-world situations, need probability declines over time and that the memory-loss rate is calibrated to match the progressive reduction in need probability (J. R. Anderson & Schooler, 1991). The present experiments were designed to examine the influence of the slope of the need-probability curve on the slope of the retention curve. On each of several trials, subjects memorized a list of digits, then retained the digits in memory for 1, 2, 4, 8, or 16 sec. Some trials ended with a recall test; other trials ended with the message, “no test.” In Experiment 1, the likelihood of encountering a memory test (i.e., the need probability) was made to either increase or decrease as the retention interval increased; in Experiment 2, need probability either was flat (invariant across retention intervals) or decreased as the retention interval increased. The results indicated that the shape of the need-probability curve influenced the slope of the retention curve (Experiment 1) and that the effect became larger as the experimental session progressed (Experiment 2). The findings support the notion that memory adapts to need probabilities and that the rate of forgetting is influenced by the slope of the need-probability curve. In addition, all of the forgetting curves approximated a power function, suggesting that need probability influences the slope but not the form of forgetting.  相似文献   
59.
We all face resource-allocation tasks, yet little is known about how people make resource-allocation decisions. Three earlier papers (Langholtz, Gettys, & Foote, 1993, 1994, 1995) established that people can intuitively solve technical two-dimensional resource-allocation problems, where allocations are made on a continuous scale, reaching solutions that approach the optimum solution determined with Linear Programming (LP). In this research we expand our understanding of how people make resource-allocation decisions by examining how people perform complex but commonplace problems using a discrete scale where optimal solutions are determined with Integer Programming. We also contrast performance under conditions where progressively unequal scheduling is required to reach the optimum solution. The data show people can achieve solutions that provide most of the payoffs found with LP, even when they are faced with a complicated three-dimensional problem, but there is a tendency toward equal scheduling under all conditions.  相似文献   
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