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111.
Considerable research has been conducted on grade inflation and its pervasiveness. Given the significance of grade inflation on the quality of the educational experience and the reputations of colleges and universities, efforts to assess its presence and underlying causes should be supported and solutions developed. Because periodic changes in average grades in the short term may be anomalous, mean grade point averages (GPAs) for 262 undergraduate courses at a Liberal Arts college were examined for trends across a 10-yr. period. Analysis showed higher grades appeared within two of the colleges' four academic units, although the reasons remained unclear. Tentative explanations are explored.  相似文献   
112.
Differences in perceptions of comfort, exertion, balance, and heart rate were investigated with two types of backpack. Subjects were 20 male volunteers (M age = 24.3 yr., SD: 3.6, M height = 180.02 cm, SD: 8.0, and M weight = 86.46 kg, SD: 14.84). Following oral briefing and practice trials, each subject was fitted at random with either an internal- or external-frame backpack containing 18.2 kg. By random, cross-over design, subjects completed a 30-m simulated hiking trial consisting of 16 separate obstacles designed to resemble actual off-trail hiking. Trials were conducted in a controlled environment with the walking intensity regulated by a metronome. Upon completion of each trial, the subjects rated the experience on perceived comfort, balance and stability, and rating of perceived exertion. Heart rate was recorded immediately prior to and following each trial. Analysis yielded a significant difference only on rating of perceived exertion in favor of the internal-frame backpack. Under limited circumstances, these data suggest that both types of backpacks provide similar comfort and balance and stability; however, internal frames in backpacks may reduce perceived exertion during short, demanding hikes.  相似文献   
113.
In a sample of 18 industrialized nations, measures of national character did not improve the power of socioeconomic variables in predicting unemployment rates.  相似文献   
114.
This study questions the evidence that a parity rule is used during the verification of multiplication. Previous studies reported that products are rejected faster when they violate the expected parity, which was attributed to the use of a rule (Krueger, 1986; Lemaire & Fayol, 1995). This experiment tested an alternative explanation of this effect: the familiarity hypothesis. Fifty subjects participated in a verification task with contrasting types of problems (even x even, odd x odd, mixed). Some aspects of our results constitute evidence against the use of the parity rule: False even answers were rejected slowly, even when the two operands were odd. We suggest that the odd-even effect in verification of multiplication could not be due to the use of the parity rule, but rather to a familiarity with even numbers (three quarters of products are indeed even).  相似文献   
115.
Experimental rats were trained on multiple 2-odor discrimination tasks, whereas controls were given repeated sessions on Task 1 and then were tested on a novel 2-odor task. Experimental rats showed strong positive transfer across problems and approached errorless or near-errorless learning. Control rats maintained near-perfect performance on Task 1 but performed at chance on initial trials when tested with novel odors. Thus, the near-errorless terminal performance of experimental rats was a function their having been trained on multiple problems and was not simply the result of eliminating "disruptive response tendencies" (I. C. Reid & R. G. M. Morris, 1992). Results support the view that when rats are trained on a series of 2-odor discrimination tasks, they acquire a strategy or rule that allows them to solve new problems with few or no errors.  相似文献   
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Children have been shown to prefer faces rated as highly attractive by adults over faces rated as quite unattractive. We investigated to what extent this agreement holds not only for the general direction of preferences but for preference strengths as well. In a choice experiment, we presented 40 nine-year-old girls and their mothers and 40 twelve-year-old girls and their mothers with pairs of women's and girls' faces and asked the subjects to pick the face that appeared prettier to them. Preference frequencies and simple attractiveness scales derived from these preference frequencies by fitting the Bradley-Terry-Luce rule (Luce, D. R. (1959). Individual choice behavior: a theoretical analysis. New York: Wiley) were compared across subject groups. For the women's faces, we found no difference in preferences between nine-year-olds, twelve-year-olds, and adults, neither in direction nor in strength. For the girls' faces, we also found no major differences in preference direction, however, we did find reliable differences in preference strengths. To a considerable part these differences were due to the fact that the children showed less pronounced preferences between face stimuli than the adults. These results suggest a role of developmental factors in the perception of facial attractiveness.  相似文献   
119.
OBJECTIVE: To promote greater compliance in using prescribed infant apnea monitors among families with a medically at-risk infant. Eight consecutively referred non-compliant families were treated by a medical social worker who provided educational, behavioral prompting, and case management services. In six families results were evaluated with A-B single case research designs, and in two families A-B-A designs were used. Enhanced compliance followed intervention with all eight families. Clinically satisfactory compliance permitting the pediatrician to safely discontinue monitor use occurred in five of the eight families. Simple behavioral and case management interventions show great promise in promoting caregiver compliance with using home-based infant apnea monitors.  相似文献   
120.
Attention and joint attention in preschool children with autism   总被引:13,自引:0,他引:13  
Three experiments examined the role of attention in explaining dyadic (child-adult) and triadic (child-adult-object) joint attention difficulties in autism. Experiments 1 and 2 investigated children's ability to orient to an adult's attention bid and to follow the direction of a human or nonhuman cue. Experiment 3 tested ability to disengage and shift attention to objects. Results showed autism-specific difficulties at both dyadic and triadic levels. Children with autism were less responsive than developmentally delayed controls in orienting to attention bids and in following a human head-turn cue yet had no difficulty in shifting attention and were faster overall in orienting to targets. Results suggest a specific developmental delay in which children with autism rely on the presence of objects in the visual field to guide action. The relation between this problem and autistic children's difficulties with human communicative signals is discussed.  相似文献   
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