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881.
882.
Subjects were given a noncontradictory set of propositions followed by a sentence which they had to accept as true. This sentence introduced an inconsistency which the Ss were required to resolve by assigning truth values to the statements. In previous work, the authors found that when forced to choose between the truth of a generality (All A's are B's) and that of a particular fact (This Y is a Z), subjects consistently rejected the fact in favor of the generality. Affirmative generalities were accepted more often than negative ones, and those expressing class-inclusion were accepted more often than those expressing property-assignment. The present experiments show that preference for generalities is independent of (a) the superficial form of the generality (i.e., the surface presence of a quantifier), (b) the polarity of the contrasted fact (affirmative or negative), and (c) the terms used to express the relations (is a and has a). The preference for reasoning with generalities is enhanced when they assert generally known facts which are not delimited in space or time. A theoretical treatment of the results employing the calculus of modal logic was explored. 相似文献
883.
Signal frequency and shock probability as determinants of prolonged vigilance performance in rhesus monkeys
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Norman A. Krasnegor Joseph V. Brady 《Journal of the experimental analysis of behavior》1972,17(1):113-118
The effects of changing signal frequency on a prolonged vigilance task were investigated by systematically increasing the average inter-trial interval between successive signals. During a 6-hr watch, vigilance performance remained constant when the rate of signal presentation was 40, 20, and 10 per hour. When the rate of signal presentation was reduced to 7 or 4 per hour, marked decrements in detection performance were observed. Similar vigilance decrements occurred when the average rate of signals per hour was kept constant (10 per hour) and the probability of receiving a shock for missing a signal was systematically varied. The results of this study indicate the importance of reinforcement factors in the control and maintenance of vigilance performance. 相似文献
884.
Joseph M. F. Jaspars John. P. Van De Geer Henri Tajfel Nicholas Johnson 《European journal of social psychology》1972,2(4):347-369
The present study consists of three related experiments which are concerned with the development of national attitudes in children between the ages of seven and twelve. It was predicted on the basis of a structural interpretation of Allport's three-stage developmental theory of prejudice that national attitudes will increase at first due to increasing consistency of judgment and decrease afterwards due to cognitive differentiation. The hypothesis is partially confirmed with respect to the attitudes of children towards other countries but not confirmed with respect to the attitudes of children towards people who are perceived as foreigners. A tentative explanation is offered for the last finding. It was shown moreover that the attitudes of older children display more cognitive balance than those of younger children. In connection with the last problem, a quantified modification Bf Heider's theory of balanced states was introduced. 相似文献
885.
Joseph W. Cullen David E. Scarborough 《Integrative psychological & behavioral science》1972,7(3):151-163
KCl water preference was examined in diet-replete, sodium-and sodium—potassium-deficient postpubertal rats of different ages. While diet-replete rats displayed a KCl preference-aversion profile similar to that found using other salts, when retested 30 days later, these same animals had no KCl preference. Na-and Na—K-deficient rats preferred KCl over a broad range of concentrations when tested in early postpuberty and the Na—K-deficient group had a markedly reduced KCl preference threshold (0.12%) when compared to all other groups in the study. But Na-and Na—K-deficient rats older by 2 1/2 months did not prefer KCl. The notion of specific food hungers can be invoked to account for some of the preferences. But hedonics, age and KCl experience must also be considered based on (1) the quantities of KCl consumed, (2) the preference reversals within animals, as well as (3) the significantly increased heart—and kidney—body weight ratios in the rats with the greatest KCl preference. 相似文献
886.
The apparent heaviness of a set of 40 cylindrical objects was scaled by the method of magnitude estimation. The objects varied in weight, volume. and density. There were three main conclusions: (1) For any constant volume, heaviness grows as a power function of weight; the larger the volume. the larger the exponent of the power function. The family of such power functions converge at a common point in the vicinity of the heaviest weight that can be lifted. (2) For any constant density (i:e., weight proportional to volume), heaviness does not grow as a power function of weight. (3) For any constant weight, heaviness decreases approximately as a logarithmic function of volume; the constants of the log function depend systematically on the weight of the object. The outcome furnishes a broad quantitative picture of apparent heaviness and of the size-weight illusion (Charpentier’s illusion). 相似文献
887.
Joseph L. Fleiss 《Psychometrika》1970,35(2):143-162
A model for a score based on an interview is presented which identifies the effect due to the subject, to the manner in which the interviewer tends to conduct his interviews, to the criteria he tends to use in scoring subjects' responses, to the compromises he tends to adopt between the demands of interviewing and those of scoring, and to chance errors. A suggested experimental design calls for each ofK investigators to interview a different sample ofN subjects, but for all investigators to score each subject. The drawing of inferences when interest is only in theK participants in the reliability study is considered, and a numerical example is given.This work was supported in part by grant DE R01 00793 from the National Institute of Dental Research, and in part by grants MH 08534 and MH 09191 from the National Institute of Mental Health, and forms part of the author's Ph.D. dissertation at Columbia University. The guidance provided by Professor T. W. Anderson is gratefully acknowledged. 相似文献
888.
889.
Cotherapy in a training relationship with a senior therapist/supervisor and a trainee/junior leader is presented. A structured training year with planned sessions for the junior leader to lead the group alone, as well as intensive supervision, is described. The training relationship is seen as evolving into an egalitarian, collegial working relationship. An incidental benefit of this cotherapy approach is that additional opportunities are provided for group members to work through attitudes, feelings, and behaviors associated with attachment, interpersonal relationship (autonomy and affiliation), separation, and loss. Potential drawbacks and applications are also noted.The authors express their appreciation to the many group members and cotherapists whose experiences provided the stimulation and clinical material for the present formulation. 相似文献
890.
We consider the issue of what an agent or a processor needs to know in order to know that its messages are true. This may be viewed as a first step to a general theory of cooperative communication in distributed systems. An honest message is one that is known to be true when it is sent (or said). If every message that is sent is honest, then of course every message that is sent is true. Various weaker considerations than honesty are investigated with the property that provided every message sent satisfies the condition, then every message sent is true.This is an expanded version of a paper that appears in the Proceedings of the Second IEEE Symposium on Logic in Computer Science, 1987. 相似文献