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21.
Rats were trained on an appetitive discriminated operant procedure according to a blocking design, in which training with a compound stimulus (A + B) was given with or without prior training with A alone. Stimulus B was then presented in compound with a new stimulus (B + C compound). The ability of Stimulus B to block acquisition of control by Stimulus C was decreased by B having itself been blocked by A during the prior training. The results imply that the mechanism of blocking during the initial blocking procedure was a reduced association between Stimulus B and the reinforcer, and not a performance deficit such as that postulated by comparator models of learning.  相似文献   
22.
In the experiment reported here the primary hypothesis proposed, which was supported by the data, was that subjects performing a two-choice self-paced serial RT task would learn to change their strategy of perceptual analysis of signals presented to them as they became progressively more practised. Early in practice each signal is identified as a particular state of the display and an appropriate response is then made. Well practised subjects, however, select their responses by reference to the change or constancy between successive displays. This strategy implies that the assumptions made by the generally accepted simple S-R connectionist model of two-choice serial RT may be quite misleading, since the choice of any particular response must be determined not only by the display state but also by what the previous response had been.  相似文献   
23.
The Hatfield Polytechnic, Hatfield, Herts ALIO 9AB, England The experiment utilized a serial choice reaction time (RT) paradigm in which only one alphanumeric stimulus was presented per trial, and the target set consisted of a single identified item. The categorical relationship between the target and nontarget items was varied as a property of blocks of trials. Target and nontarget RTs were smaller when the specified target item (e.g., the number 6) was categorically distinct from the nontargets (e.g., letters) than when it was from the same category (e.g., digits). The processing of catch-trial stimuli (items from the alternate category to the nontargets) and homographie category-ambiguous items was inhibited only in the former, between-category, condition. The results are contrasted with those obtained in visual search tasks. They suggest that a “locational-cue” explanation of alphanumeric category effects is inadequate.  相似文献   
24.
A single-subject experimental design was used to investigate the feasibility of applying non-invasive laboratory instrumentation for examining speech physiology to assessment and biofeedback-based remediation of stuttering. Physiologic assessment facilitated the development of behavioral goals directed at changing respiratory and phonatory behaviors for this subject. Visual biofeedback therapy produced reduction in respiratory discontinuities and increased phonatory continuity, concomitant with reduced perceivable molar dysfluency. Methods used in this case illustrate a variety of options and problems related to clinical use of instrumentation. Results suggest that signals which represent respiratory, phonatory, and articulatory physiologic events may be clinically practical for evaluating and altering perceivable dysfluency.  相似文献   
25.
A FAITH FOR ALL SEASONS:ISLAM AND WESTERN MODERNITY. By Shabbir Akhtar. London: Bellew Publishing, 1990. 251pp. Hb. £25.00. ISBN 0–947792–41–4.  相似文献   
26.
The correlation between short-term retention of the outcome of the preceding response and overall learning proficiency was investigated for serial reversal learning. Pigeons were trained to asymptote on a serial reversal problem and then were presented a percentage reinforcement schedule where only some correct trials were rewarded. Nonrewarded correct trials were treated exactly as incorrect trials. The difference in error probability following the two types of correct trials was then used as a measure of short-term retention. When intertrial intervals (ITI) were short (6 sec), substantial differences occurred. When the ITI's were increased, the difference in accuracy declined regularly to no difference at an ITI of 60 sec. This demonstration of a short-term retention gradient, coupled with the finding that overall reversal learning was much better with the shorter ITI's, suggests that a primary mechanism of improvement in serial reversal learning is the acquisition of a conditional discrimination based on the outcome of the preceding response.  相似文献   
27.
28.
This paper proposes an approach for strategic revenue management under uncertainty for real estate projects. It integrates three modelling techniques: first, artificial neural network integrated support vector machines for forecasting the profit and loss‐making real estate residential projects; second, analytical network process approach using decision making trials and evaluation laboratory methodology for establishing interrelationships among factors; and third, multiobjective genetic algorithm approach for obtaining optimal numbers and types of apartments in a real estate project. We compare the respective revenues generated with the new number of apartments and price from the suggested revenue maximization model and that of the old practiced one through a case study of India. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
29.
The sociological literature has produced a remarkably consistent picture of the quantitative patterns of religious disaffiliations in Western countries. This article argues, and demonstrates, that strong changes in a social context may lead individuals to disaffiliate rapidly, leading to very different aggregate effects from those in the “western model.” We use the unique situation of the separation of Germany from 1949 to 1989 and its subsequent reunification as a “natural experiment” to show just how much the relationships routinely found can be disrupted under changed conditions. The state socialist “treatment” affected religious disaffiliations in East Germany profoundly as it (a) made disaffiliations 10 times more probable in the East than in the West in the 1950s and 1960s, (b) shielded East German church members from factors that led to mass disaffiliations in the West in the late 1960s and early 1970s, (c) reversed the education‐disaffiliation link in the East, thus making disaffiliation more likely among the less educated, and (d) led to an especially strong increase in disaffiliations in the East right after the reunification  相似文献   
30.
In jurisdictions throughout the United States, thousands of sexual assault kits (SAKs; also known as a “rape kits”) have not been submitted by the police for forensic DNA testing. DNA evidence may be helpful to sexual assault investigations and prosecutions by identifying perpetrators, revealing serial offenders through DNA matches across cases, and exonerating those who have been wrongly accused. This paper describes a longitudinal action research project conducted in Detroit, Michigan after that city discovered approximately 11,000 untested sexual assault kits in a police department storage facility. We conducted a root cause analysis to examine individual, organizational, community, and societal factors that contributed to the development of the rape kit backlog in Detroit. Based on those findings, we implemented and evaluated structural changes to increase staffing, promote kit testing, and retrain police and prosecutors so that cases could be reopened for investigation and prosecution. As we conducted this work, we also studied how this action research project impacted the Detroit criminal justice system. Participating in this project changed stakeholders’ attitudes about the utility of research to address community problems, the usefulness of DNA evidence in sexual assault cases, and the impact of trauma on survivors. The results led to new protocols for SAK testing and police investigations, and new state legislation mandating SAK forensic DNA testing.  相似文献   
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