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131.
On fixed-interval or response-initiated delay schedules of reinforcement, the average pause following food presentation is proportional to the interfood interval. Moreover, when a number of intervals of different durations occur in a programmed cyclic series, postreinforcement pauses track the changes in interval value. What controls the duration of postreinforcement pauses under these conditions? Staddon, Wynne, and Higa (1991), in their linear waiting model, propose control by the preceding interfood interval. Another possibility is that delay to reinforcement, signaled by a key peck and/or stimulus change, determines the subsequent pause. The experiments reported here examined the role of these two possible time markers by studying the performance of pigeons under a chained cyclic fixed-interval procedure. The data support the linear waiting model, but suggest that more than the immediately preceding interfood interval plays a role in temporal control.  相似文献   
132.
Survey research with diverse cultural and ethnic minority groups is a complex and challenging endeavor that confronts the researcher with problems related to linguistic and conceptual equivalence and measurement as well as problems related to difficulties that respondents have with the sociocultural dimensions of the survey/interview process. One way to improve the quality of cross-cultural surveys and to insure that the findings are culturally relevant and accurate is to combine qualitative and quantitative methods. This paper proposes that certain qualitative techniques from cognitive science, specifically cognitive anthropology and cognitive psychology, are particularly well suited to being combined with survey research. These techniques provide information corresponding to the underlying thought processes of respondents and enable researchers to better understand how different cultural and ethnic groups construe the world. The information obtained can be used improve the formulation of survey questions, design and structure questionnaire formats to coincide with the way particular groups organize concepts, and help researchers understand difficulties respondents may have with the survey/interview process. In addition, the techniques produce data that are easily codifiable and more manageable than traditional qualitative techniques including participant observation and in-depth interviews.  相似文献   
133.
The Suicide Probability Scale (SPS), the Perceived Social Support (PSS) from Friends (PSS-Fr) and Family (PSS-Fa) scales, and the Scale for Interpersonal Behavior (SIB) were translated into Swedish and their reliability was estimated in a university student sample. The reliability coefficients indicated that both subscales and the total scales of the SPS, PSS, and SIB possess highly adequate reliabilities. The intercorrelations among the subscales and between the subscales and the total scales were found to be highly significant. The results of the study supported the use of SPS, PSS-Fr and PSS-Fa, and the SIB as reliable methods for assessing suicide risk, perceived social support from friends and family, and assertive behavior.  相似文献   
134.
Delayed and current stimulus control in successive discriminations   总被引:1,自引:1,他引:0       下载免费PDF全文
In a successive discrimination in which successively alternating red and green hues signaled component variable-interval schedules, sensitivity of the ratio of responses in the two components to variation in the component reinforcer ratio decreased systematically during the course of the component. This decrease in stimulus control or discrimination over the course of the component was shown to be the result of delayed control of responding during the component by the stimulus transition between components. When the red–green stimulus transition was altered by interpolating a white stimulus at the end of each 60-s component, discrimination at the beginning of the component (measured by the power-function exponent for sensitivity to reinforcement) was reduced. Conditions with the white stimulus inserted in other quarters of the component indicated that the current discriminative stimulus exerts control over responding throughout the component, whereas during about the first half of the component, response differentials are influenced by the transition between discriminative stimuli.  相似文献   
135.
This paper suggests that medical education be revised to assist in diffusing potential ethical dilemmas that arise during health care provision. A revised medical education would emphasize the role of the humanities in the training of physicians, especially in light of recent critiques of the canonical scientific model in general, and more specifically in the use of that model for medical training and practice.I wish to thank Dr. Mary Ann Cutter and Melissa M. Amaro for their critical suggestions.  相似文献   
136.
It is argued that the manner in which we teach science in the high schools represents an outdated positivistic conception of science. The standard presentation of a year of each of chemistry, biology and physics should be replaced by an integrated science plus history, philosophy, and sociology of science which would take a total of three years to complete. A proper appreciation for the true nature of science is essential to the continued health of the scientific enterprise.  相似文献   
137.
Kevin J. Sharpe 《Zygon》1990,25(1):105-122
Abstract. David Bohm's thinking has become widely publicized since the 1982 performance of a form of the Einstein-Podolsky- Rosen (EPR) experiment. Bohm's holomovement theory, in particular, tries to explain the nonlocality that the experiment supports. Moreover, his theories are close to his metaphysical and religious thinking. Fritjof Capra's writings try something similar: supporting a theory (the bootstrap theory) because it is close to his religious beliefs. Both Bohm and Capra appear to use their religious ideas in their physics. Religion, their source for physical hypotheses, provides the motivation to develop and uphold them.  相似文献   
138.
A multidisciplinary group of genetic and other professionals discuss a complex case of familial conflict over access to genetic information. One twin wishes to know the results of her deceased mother's tests for BRCA1 mutations; a second twin objects to researchers making this information available. As the case discussion unfolds, the apparent facts of this case are called into question and the lines of ethical certainty become less clear.  相似文献   
139.
140.
自由回忆和线索回忆测验中的系列位置效应   总被引:3,自引:1,他引:2  
吴艳红  朱滢 《心理科学》1997,20(3):217-221
本文以96个中国汉字为材料,使用自由回忆和线索回忆测验方法,对20名被试进行6组分测验和最后所有汉字的总测验。发现自由回忆分测验中存在明显的系列位置效应,总测验出现负近因现象;线索回忆分测验也表现出明显的系列位置效应,但最后的总测验没有出现负近因现象。上述结果验证了Bjork和Whitten(1974)提出的顺序或情景理论。  相似文献   
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