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171.
This case study of an inter-university controversy over the publication of research from an interdisciplinary social science project on the forced migration and long-term internment of West Coast Japanese-Americans during World War II shows some of the difficulties of maintaining ownership of research materials. In this particular instance the junior employee was able to override his seniors' demand for control of the dissemination of research results by playing on the concerns about even appearing to suppress work for political reasons. The paper discusses conflicting norms of science and rhetorics of justification ranging from proprietary self-interest through "good science" to "the national interest" and onto "the needs of a free society."  相似文献   
172.
The item characteristic curve (ICC), defining the relation between ability and the probability of choosing a particular option for a test item, can be estimated by using polynomial regression splines. These provide a more flexible family of functions than is given by the three-parameter logistic family. The estimation of spline ICCs is described by maximizing the marginal likelihood formed by integrating ability over a beta prior distribution. Some simulation results compare this approach with the joint estimation of ability and item parameters.IRCAMThe research reported in this paper was supported by Grants APA320 and A4035 from the Natural Sciences and Engineering Research Council of Canada. It was also supported by Contract No. F41689-82-C-10020 from the Air Force Human Resources Laboratory to Educational Testing Service. The author wishes to thank M. Abrahamowicz for his assistance and R. Darrell Bock for providing the parameters for the items used in the simulations.  相似文献   
173.
This study examines the relationship between Type A behaviour and smoking. Data were gathered from a random sample of 100 undergraduate male daily smokers, with a mean age of 21.2 years (SD = 2.72), using the Type A Behaviour Scale (Bortner and Rosenman, 1967). Results reveal that Type A smokers are heavier daily consumers of cigarettes than Type B smokers (t = 2.90, p less than 0.01). The observed relationship between smoking and Type A behaviour remains significant even when the influence of aggression in partialled out. The need to further investigate the interplay of genetic and non-genetic predispositions, and smoking in the incidence of coronary heart diseases (CHD) is suggested.  相似文献   
174.
This experiment provides a test for the common sense knowledge that moderate physical exercise leads to mood improvement. Furthermore, it was tested whether light exercise intensifies negative feeling states or alleviates them. 30 female and 30 male students of psychology served as subjects (mean age 25.3 years, SD = 4.8). After being exposed to a mood induction procedure designed to elicit either a positive or negative feeling state, the subjects had to pedal a bicycle ergometer with 0, 50 or 75 Watt load. Cardiovascular variables and self-reports of mood states were assessed during a baseline period, after the mood induction, following the ergometer exercise, and after a follow-up period. The mood induction procedures were successful, but only for a short duration. Physiological activation was observed according to the ergometer loadings. Moderate physical exercise led to an increase of positive feeling states (Concentration) and a decrease of negative feeling states (Tiredness) in the follow-up period. Corresponding changes in tension related states could not be observed, probably due to the weakness of the mood induction procedure employed and the low level of energetic activation reached.  相似文献   
175.
Dyslexic and normal control subjects memorized simple line patterns inside a grid and subsequently judged whether an "X" would have fallen on the pattern had it been present in an empty grid. The patterns were letters and novel shapes. The grids were presented to the left visual field, to the right visual field, or in central vision. Dyslexic subjects had difficulty generating images of multipart patterns, but this deficit was limited to letters. The findings suggest that dyslexics may have selective difficulty integrating visual information stored in long-term memory.  相似文献   
176.
Potential members of the International Fluency Association (IFA) were polled regarding their fluency interests and perceived priorities for the organization during the year it was founded (in 1990). Results from 201 respondents indicated that a need for the IFA existed among researchers, clinicians, and representatives of self-help organizations for people who stutter. Improving the quality of treatment for those who stutter was considered the highest priority by all three groups. Researchers were of the opinion that the Journal of Fluency Disorders should be of higher quality than it had been in the past, and clinicians were most interested in reviews of new and relevant materials.  相似文献   
177.
This study focused on adult age differences in the characteristics and quantity of elaborations produced during a prose recall task. Young (M = 24.3 years) and older (M = 67.9 years) adults were tested in 3 same-age, same-gender group size conditions: individual, dyad, and tetrad. Elaborations, which are statements not contained in the text but not inconsistent with it, were divided into 2 major categories. Denotative elaborations included statements that were closely related to the text and filled in gaps in the stories. These elaborations were equally produced by young and older adults and were significantly correlated with gist recall performance. Annotative elaborations were evaluative and interpretive comments. These statements were more frequently produced by older adults but were not correlated with recall performance. Young and older adults had different patterns of annotative elaboration production across group size conditions.  相似文献   
178.
179.

A differential conditioning study examined whether an acoustic startle probe, presented during extinction of an aversively conditioned visual stimulus, potentiated the reflex eyeblink response in humans and whether this potentiation varied with the change in affective valence of the conditioned stimulus. Sixty college students were randomly assigned to view a series of two slides, depicting either unpleasant/highly arousing, unpleasant/moderate arousing, neutral/calm, pleasant/moderate arousing or pleasant/highly arousing scenes and objects (duration: 8 sec). During preconditioning (8 trials) and extinction (24 trials) acoustic startle probes (white noise bursts [50 ms; 95 dBA] were administered during and between slide presentation). During acquisition (16 trials) CS+ was reinforced by an electric shock. Startle response magnitudes significantly increased from preconditioning to extinction and were substantially larger to CS+. Conditioned startle reflex augmentation linearly increased with the pleasantness of the slides. Furthermore, subjects showed a greater post-conditioning increase of judged aversiveness to slides that they had previously reported to be more pleasant, exactly paralleling the startle reflex results.

  相似文献   
180.
Undermining the Zeigarnik effect: Another hidden cost of reward   总被引:1,自引:0,他引:1  
Forty college students participated in a study ostensibly designed to obtain measures of the hemispheric activity while they worked on a spatial reasoning task. In fact, our true interest was in determining whether subjects would return to the spatial reasoning task once the hemispheric recordings were completed. Subjects would normally be expected to return to the task by virtue of the Zeigarnik effect because no subject completed the task during the “hemispheric recording” phase. The manipulation involved telling one group of subjects that they would be paid $1.50 for participating in the study (expected reward group). The remainder of the subjects were not led to expect the reward (unexpected reward group). The result was that 86% of the unexpected reward subjects but only 58% of the expected reward subjects (p < .05) manifested the Zeigarnik effect. This differential tendency to return to the task was further reflected in time differences. The average unexpected reward subject spent 3 min 48 sec of a five-minute free-choice period at the task, whereas the average expected reward subject spent only 2 min 20 sec (p < .05). Reward expectancy, therefore, led to an undermining of the Zeigarnik effect. This observation supports Condry's prediction that rewarding performance at a task can lead to premature task disengagement.  相似文献   
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