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991.
Two-key concurrent responding was maintained for three pigeons by a single variable-interval 1-minute schedule of reinforcement in conjunction with a random number generator that assigned feeder operations between keys with equal probability. The duration of blackouts was varied between keys when each response initiated a blackout, and grain arranged by the variable-interval schedule was automatically presented after a blackout (Exp. I). In Exp. II every key peck, except for those that produced grain, initiated a blackout, and grain was dependent upon a response following a blackout. For each pigeon in Exp. I and for one pigeon in Exp. II, the relative frequency of responding on a key approximated, i.e., matched, the relative reciprocal of the duration of the blackout interval on that key. In a third experiment, blackouts scheduled on a variable-interval were of equal duration on the two keys. For one key, grain automatically followed each blackout; for the other key, grain was dependent upon a response and never followed a blackout. The relative frequency of responding on the former key, i.e., the delay key, better approximated the negative exponential function obtained by Chung (1965) than the matching function predicted by Chung and Herrnstein (1967).  相似文献   
992.
Some punishing effects of response-force   总被引:1,自引:1,他引:0       下载免费PDF全文
The present experiment explored the punishing effect of different response-force requirements by means of a two-operant design analogous to a two-component chain schedule. The first component of the chain required a lever pull through 0.25 in. (0.64 cm) at 1 lb (4.45 N) of force. The second component required a lever pull through an additional 0.75 in. (1.90 cm) with the force varied between sessions from 1 lb to 50 lb (4.45 N to 223 N). Completion of the second component of the chain was reinforced after variable intervals averaging 1 min. The average rate of first-component response decreased as the force requirement for second-component responses was increased. This rate reduction did not appear to be due to increased response duration, “fatigue”, or differing rates of reinforcement. If the force requirement for the second-component response is viewed as a consequence for the first-component response, then the results of the experiment show that a high force requirement is a punisher.  相似文献   
993.
Food-deprived pigeons responded under a 10-min fixed-interval schedule of food presentation. During even-numbered minutes of the schedule, the discriminative stimuli were the same as those present when food was delivered. During odd-numbered minutes there was either a change in keylight color or a change in overhead illumination, either for the entire duration of the odd-numbered minutes, or for 3-sec after each response. Responding during even-numbered minutes showed the usual pattern of positive acceleration; responding during odd-numbered minutes was similarly graded, but rates were much lower. The response-rate-increasing effects of amobarbital were inversely related to control rates of responding for both even- and odd-numbered minutes. However, when the stimulus change during odd-numbered minutes was either keylight color or a change from a darkened to a brightly illuminated chamber, increases in responding were considerably less than predicted on the basis of the effects on responding during even-numbered minutes. When the stimulus change was from a darkened to a dimly illuminated chamber, control rates of responding changed little, but increases in responding during odd-numbered minutes after amobarbital were considerably greater, and of the approximate order expected on the basis of control rate.  相似文献   
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The impact of professional negotiations on the current educational scene is examined and related to clarification of the school counselor role. Role confusion continues in the school situation, and negotiations may well be the way to bring about a change in the status quo. Negotiations for counselors are explored from the standpoints of dimensions of negotiations, implementation of negotiations, and attitude of professional associations. Conclusions are that negotiations have significant implications for counselor role delineation.  相似文献   
999.
A work experience project for low income adults is described. “Counselors” in this project were found to have little experience; little training in interviewing, statistics, psychological analysis, or other guidance and counseling techniques; and inadequate supervision. Results on aptitude tests were reported on the average 26 days after test administration. Occupational information was sadly lacking. The question is raised: When is a counselor… ?  相似文献   
1000.
Today's college students are finding an increasing need for legal information. At California State College, Los Angeles, a lawyer from the community was retained by the college counseling center to consult with students who had legal questions. During the academic year 1968-69, 302 students took advantage of this service. Although most of their questions dealt with selective service, other areas of concern included landlord-tenant matters, domestic relations, and criminal and civil law. Student reactions were sampled by means of a questionnaire. The general response was highly favorable, thus supporting the need for a legal counseling service on the college campus.  相似文献   
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