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51.
Choice and multiple reinforcers   总被引:3,自引:3,他引:0       下载免费PDF全文
Pigeons chose between equivalent two-component mixed and multiple terminal-link schedules of reinforcement in the concurrent-chains procedure. The pigeons preferred the multiple schedule over the mixed when the components of the compound schedules were differentiated in terms of density of reinforcement, but the pigeons were indifferent when the components were differentiated in terms of number of reinforcers per cycle. Taken together, these results indicate that a local variable, the interval to the first reinforcer, but not a molar variable, the number of reinforcers, was sufficient to differentiate the components and thereby evoke preference.  相似文献   
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Recent research has shown that academic choice and achievement may be partly a function of the student's standing on the field-dependence-independence cognitive-style dimension. The results of two longitudinal studies suggest that information about field dependence-independence may be of value for student guidance in the medical setting. The first, a study of college undergraduates who early expressed an interest in medicine, showed that these cognitive styles play a discernible role in determining who will eventually enter medical school. The second, a study of medical students, showed that field-dependent and field-independent students subsequently tend to choose different medical specialties. These results are consistent with cognitive-style theory, which proposes that field-independent people will choose vocations that require cognitive restructuring skills, whereas field-dependent people will choose vocations that require greater social-interpersonal involvement.  相似文献   
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Two experiments examined the effect of time on causal attributions. In Experiment I, subjects who described themselves into a tape recorder assumed more personal responsibility for their behavior after 3 weeks' time than others who explained their behavior immediately after its occurrence. In Experiment II, actor-subjects took part in a getting acquainted conversation and explained their behavior more dispositionally and less situationally after 3 weeks' time than they had initially, while observer-subjects experienced no change over time. Results were interpreted in terms of an altered self-perspective in memory and the diminished salience of situational details over time.  相似文献   
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This study compared the follow-up incidence of court-recorded nonstatus offenses for three groups of adolescent children. These children had been seen 2 to 9 years earlier for problems with aggression in the home (N = 21), for stealing problems (N = 25), or for normative comparisons (N = 14). The results showed that 77% of the children with stealing problems had court-recorded offenses. This was significantly higher than the aggressive children, whose rate did not differ from the normative sample. These findings suggested that young aggressive children were not at risk for adolescent court contact. Instead, it was the young child with identified stealing problems who was highly likely to become an official delinquent. It also appeared that parental reports of stealing events constituted a predictive measure of later criminal acts.  相似文献   
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Twenty subjects were tested on their ability to recognize simple tunes from which rhythm information had been removed. Only the first phrase of each tune was presented. The purpose of the experiment was (a) to determine whether stimuli containing only high harmonics can evoke a sense of musical pitch, and (b) to provide a set of data in normal subjects with which the performance of deaf subjects whose auditory nerve is stimulated electrically can be compared. Each subject was tested on five sets of stimuli presented in a counterbalanced order. These stimuli were (I) pulse trains high-pass filtered at 2 kHz, with repetition rates in the range of 100-200 p.p.s.; (2) as in (I) but high-pass filtered at 4 kHz; (3) sinusoids with musical intervals compressed, so that the “octave” was a ratio of I:I·3; (4) sinusoids with the musical intervals expanded, so that the “octave” was a ratio of I:4; (5) sinusoids of a constant frequency in which the normal frequency changes were translated into intensity changes, each semitone being represented by a 3 dB change in level. The results indicate that a pattern of intensity changes does not support tune recognition, and that, although the pitch contour alone allows reasonable performance, subjects do use musical interval information in recognizing tunes. Stimuli containing only high harmonics can provide such interval information, and thus can evoke a sense of musical pitch. Preliminary results from a deaf subject stimulated electrically with an electrode on the surface of the cochlea indicate that such stimulation can also evoke a sense of musical pitch. It is concluded that musical pitch information can be carried in the time-pattern of nerve impulses in the auditory nerve.  相似文献   
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The challenge of providing high-quality public defense services continues to be a concern at federal, state, and local levels. Some scholars have alluded to a potential solution in client-centered representation, but research in this area is sparse at best. Such a lack of understanding leaves in its place speculation, particularly as to the potential importance of client perceptions in shaping broader system legitimacy. To fill this gap and create an empirical platform for future research, an exploratory pilot study was launched with the Hamilton County, Ohio Public Defender's Office, which used mixed methodologies to assess client attitudes toward public defenders as a potential resource for aiding the improvement of indigent representation. Findings from this pilot study suggest that there are five factors a public defense attorney should address that may prove to be very important in obtaining client satisfaction and cooperation: engaging the client for input, listening to the client, examining the prosecutor's evidence, focusing on the client's case during meetings, and informing the client of potential consequences. Implications for practice and future research are discussed. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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