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51.
COVID-19 vaccine concerns remain high among Americans. Although recent studies have investigated the sociodemographic disparities in vaccine concerns, less attention has been given to reasons for vaccine skepticism and psychosocial factors that may explain it. The current study examined specific types of vaccine concerns among a diverse sample of college students (N = 1985) living in New York City. Participants who identified as Black, younger, with later immigrant generational status, and those with more conservative political leanings reported more vaccine concerns. Concerns regarding vaccine side effects were the most frequently reported source of concern. Reason for getting vaccinated, personal experiences with COVID, and COVID stress was also associated with vaccine concerns. Study results emphasize the importance of sociodemographic factors and COVID knowledge and stress in examining and addressing vaccine concerns.  相似文献   
52.
Preventive health practices have been crucial to mitigating viral spread during the COVID-19 pandemic. In two studies, we examined whether intellectual humility—openness to one's existing knowledge being inaccurate—related to greater engagement in preventive health practices (social distancing, handwashing, mask-wearing). In Study 1, we found that intellectually humble people were more likely to engage in COVID-19 preventive practices. Additionally, this link was driven by intellectually humble people's tendency to adopt information from data-driven sources (e.g., medical experts) and greater feelings of responsibility over the outcomes of COVID-19. In Study 2, we found support for these relationships over time (2 weeks). Additionally, Study 2 showed that the link between intellectual humility and preventive practices was driven by a greater tendency to adopt data-driven information when encountering it, rather than actively seeking out such information. These findings reveal the promising role of intellectual humility in making well-informed decisions during public health crises.  相似文献   
53.
What we usually think of as higher order skills in argumentation can be profitably viewed as systematic structures for organizing and representing information. Standard terms like line of argument, synthesis, analysis and draft can be viewed as ways of constructing, storing, and accessing data in a social context — data structures for social communication. What makes argument difficult are the multiple structures that arguers have to construct and negotiate when reading and composing. In this paper, we describe the WARRANT project, a project designed to identify data structures of written argument and to design and implement computer tools to aid in the reading and design of argument.  相似文献   
54.
Evidence has accumulated for information processing deficits in schizophrenia. The functional significance of these deficits is only beginning to be understood. There are indications that these deficits may respond to intervention. Training on deficient functions has been demonstrated to relate to improvements in performance. A treatment program of cognitive rehabilitation is deduced from the literature and induced from clinical experience. The treatment is designed to impact directly on the information processing deficits of schizophrenic patients and indirectly to ameliorate functional deficits.  相似文献   
55.
An operant simulation of foraging through baited and empty patches was studied with 4 pigeons. On a three-key panel, side keys were designated as patches, and successive opportunities to complete 16 fixed-ratio 10 schedules on side keys were defined as encounters with feeders. In a random half of the patches in any session, some of the fixed-ratio 10 schedules yielded reinforcement (baited feeders) and the other schedules yielded nonreinforcement (empty feeders). In the other half of the patches, all feeders were empty. Pigeons could travel between patches at any time by completing a fixed-ratio schedule on the center key. An optimal foraging model was tested in Experiments 1 and 2 by varying center-key travel time and number of baited feeders in baited patches. The ordinal predictions that number of feeders visited in empty patches would increase with travel time and decrease as number of baited feeders increased were supported, but pigeons visited far more feeders in empty patches than the optimal number predicted by the model to maximize energy/time. In Experiment 3, evidence was found to suggest that the number of empty feeders encountered before the first baited feeder in baited patches is an important factor controlling leaving empty patches.  相似文献   
56.
In a discrete-trial conditional discrimination procedure, 4 pigeons obtained food reinforcers by pecking a key with a short latency on trials signaled by one stimulus and by pecking the same key with a long latency on trials signaled by a second stimulus. The physical difference between the two stimuli and the temporal separation between the latency values required for reinforcement were varied factorially over four sets of conditions, and the ratio of reinforcer rates for short and long latencies was varied within each set of conditions. Stimulus discrimination varied directly with both stimulus and response differences and was unaffected by the reinforcer ratio. Sensitivity to reinforcement, estimated by generalized-matching-law fits to the data within each set of conditions, varied directly with the response difference but inversely with the stimulus difference arranged between sets of conditions. Because variations in stimulus differences, response differences, and reinforcer differences did not have equivalent effects, these findings question the functional equivalence of the three terms of the discriminated operant: antecedent stimuli, behavior, and consequences.  相似文献   
57.
Delay reduction: current status.   总被引:6,自引:6,他引:0       下载免费PDF全文
Delay-reduction theory states that the effectiveness of a stimulus as a conditioned reinforcer may be predicted most accurately by the reduction in time to primary reinforcement correlated with its onset. We review support for the theory and then discuss two new types of experiments that assess it. One compares models of choice in situations wherein the less preferred outcome is made more accessible; the other investigates whether frequency of conditioned reinforcement affects choice beyond the effect exerted by frequency of primary reinforcement.  相似文献   
58.
Eight pigeons were trained on concurrent variable-interval variable-interval schedules with a minimum interchangeover time programmed as a consequence of changeovers. In Experiment 1 the reinforcement schedules remained constant while the minimum interchangeover time varied from 0 to 200 s. Relative response rates and relative time deviated from relative reinforcement rates toward indifference with long minimum interchangeover times. In Experiment 2 different reinforcement ratios were scheduled in successive experimental conditions with the minimum interchangeover time constant at 0, 2, 10, or 120 s. The exponent of the generalized matching equation was close to 1.0 when the minimum interchangeover time was 0 s (the typical procedure for concurrent schedules without a changeover delay) and decreased as that duration was increased. The data support the momentary maximizing theory and contradict molar maximizing theories and the melioration theory.  相似文献   
59.
It is shown that IRTs information function for an item is functionally related to local versions of classical test theories' signal/noise ratio and reliability coefficient.  相似文献   
60.
This experiment measured pigeons' choices between delayed reinforcers and fixed-ratio schedules in which a force of approximately 0.48 N was needed to operate the response key. In ratio-delay conditions, subjects chose between a fixed-ratio schedule and an adjusting delay. The delay was increased or decreased several times a session in order to estimate an indifference point--a delay duration at which the two alternatives were chosen about equally often. Each ratio-delay condition was followed by a delay-delay condition in which subjects chose between the adjusting delay and a variable-time schedule, with the components of this schedule selected to match the ratio completion times of the preceding ratio-delay condition. The adjusting delays at the indifference point were longer when the alternative was a fixed-ratio schedule than when it was a matched variable-time schedule, which indicated a preference for the matched variable-time schedules over the fixed-ratio schedules. This preference increased in a nonlinear manner with increasing ratio size. This nonlinearity was inconsistent with a theory that states that indifference points for both time and ratio schedules can be predicted by multiplying the choice response-reinforcer intervals of the two types of schedules by different multiplicative constants. Two other theories, which predict nonlinear increases in preference for the matched variable-time schedules, are discussed.  相似文献   
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