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181.
Experimental control of superstitious responding in humans   总被引:8,自引:7,他引:1       下载免费PDF全文
Superstitions were demonstrated with human subjects when presses on one button were reinforced on a VI 30-sec schedule while presses on a second were never reinforced. Superstitious responding, on the second button, was often maintained because presses on that button were frequently followed by reinforcement for a subsequent press on the first button. The introduction of a changeover delay (COD), which separated in time presses on the second button and subsequent reinforced presses on the first button, reduced or eliminated the superstitious responding of these subjects. Some complex superstitions were also demonstrated with other subjects for which the COD was in effect from the beginning of the session.  相似文献   
182.
Increased eating in rats deprived of running   总被引:2,自引:1,他引:1       下载免费PDF全文
Daily food intake in rats was temporarily reduced by the introduction of an activity wheel and temporarily increased by the subsequent removal of the wheel. When this outcome is coupled with the positive relation between food deprivation and running—and food deprivation is seen as a loss of eating rather than as a physiological state—there is the suggestion that the total behavior output of the organism may be regulated as such. Specifically, when the rat is deprived of a behavior that recurrently comprises a large part of its total daily activity, an increase may occur in some other behavior.  相似文献   
183.
184.
Summary Studies of motion-detection by fish reveal two separate processes, which are hypothetically linked to different kinds of behavior. Furthermore, studies of interocular transfer with mirror-image shape discriminations also indicate two distinct mechanisms for the representation of visual directions. From these two kinds of experiment, it seems that visual processes subserving orientation of the fish to a moving object should be clearly distinguished from processes by which the fish evaluates the identity or activity of the object.
Zusammenfassung Untersuchungen der Bewegungswahrnehmung von Fischen zeigen zwei verschiedene Prozesse auf, die mit zwei verschiedenen Verhaltensweisen in Beziehung gesetzt werden. Eine Analyse des interokularen Transfers mit Unterscheidung spiegelbildlicher Formen läßt außerdem erkennen, daß zwei verschiedene Mechanismen für die Repräsentation visueller Richtungen verantwortlich sind. Aus diesen Experimenten wird geschlossen, daß jene visuellen Prozesse, welche der Orientierung des Fisches in bezug auf ein sich bewegendes Objekt dienen, scharf unterschieden werden sollten von denen, durch welche der Fisch die Identität oder Aktivität des Objektes beurteilt.
  相似文献   
185.
Modifications of the intake procedure usually employed in counseling settings were adopted in order to provide students the opportunity for immediate contact with a counselor. Elimination of the waiting list, reduction in number of missed appointments, and reduction of length of counseling came about. Staff satisfaction with the new approach has been high and there would be opposition to reverting to the scheduled initial interview. Possible changes in the type of problem or clients' readiness for problem-solving were observed.  相似文献   
186.
This paper describes a miniature solid-state timing device particularly useful for presenting repetitive signal sequences in classical conditioning experiments. The device uses transistors, silicon-controlled rectifiers, and four-layer diodes, and is powered by 20-hour rechargeable nickel-cadmium batteries. Visual monitoring is provided for the unelapsed ITI and battery charge. Ranges are; ITI, 15 sec. to 5 min., ISI, 0–50 secs., CS duration, 0.5 to 30 sec., US duration, 0.5 to 30 sec. The CS and US durations are adjustable and the onset of the latter may be at any time after the CS onset. Cycling is continuous and automatic; the outputs are in the form of relay closures.  相似文献   
187.
188.
A modification of the quartimax computation for factor rotation is described in which a hypothesized factor pattern is given to the machine along with the data. The machine uses the pattern to select the subset of variables to which it will attend when rotating in a given plane, in order to find an orthogonal solution which closely fits the hypothesis. The program also provides a measure of the goodness of this fit. The program can utilize pattern matrices that reflect only partial hypotheses as to the nature of the factors, as well as those that specify highly determined simple structure.  相似文献   
189.
A mathematical model for two-choice behavior in situations where both choices are desirable is discussed. According to the model, one or the other choice is ultimately preferred, and a functional equation is given for the fraction of the population ultimately preferring a given choice. The solution depends upon the learning rates and upon the initial probabilities of the choices. Several techniques for approximating the solution of this functional equation are described. One of these leads to an explicit formula that gives good accuracy. This solution can be generalized to the two-armed bandit problem with partial reinforcement in each arm, or the equivalent T-maze problem. Another suggests good ways to program the calculations for a high-speed computer.Support for this research has been received from the National Science Foundation (Grant NSF-G2258), the National Institute of Mental Health (Grant M-2293), and the Laboratory of Social Relations, Harvard University.We wish to acknowledge and express our appreciation for the cooperation and assistance given by Phillip J. Rulon, Albert Beaton, Wai-Ching Ho, and Donald Spearritt, who set up, programmed, and executed numerous calculations connected with the linear equations method of solution, and by Cleo Youtz for extensive calculations at every stage of the work. We also wish to thank Ray Twery and Robert R. Bush for permission to use in Table 3 some of the unpublished results of their calculations. Those calculations were made on the Illiac through the cooperation of the Digital Computer Laboratory of the University of Illinois, Dr. John P. Nash, Director.  相似文献   
190.
Evidence     
David Rynin 《Synthese》1960,12(1):6-24
Conclusion We can now see, perhaps, what merits if any this definition has. It ties in the concept of evidence with that of law, and requires us to support our claim that some fact (or statement) is evidence for another by pointing out the science, and within it the law (or what meets the tests of being acceptable as such) whose existence alone justifies us in assuming that a certain conditional statement qualifies as acceptable as nomological. Whoever claims that a certain fact is evidence for another is required to justify his assumption that there exists a certain law. That in some sense there are such justifiable assumptions is clear from the existence of natural sciences and technologies based upon them. But it will turn out that in many cases it is impossible, as of a given moment, to make out a case for the claim that a certain conditional statement, required to support the view that a certain fact is evidence for another, is nomological. In such cases we are able to draw a clear line between what someone may think or claim is evidence, and what we have reasonable grounds for accepting as such. In short the concept offers us a principle of demarcation between justified and unjustified claims for the evidential nature of facts (or statements) offered as such. If this is not a very impressive achievement still it is not wholly contemptible, considering the confusion that prevails among many people concerning the question of evidence.  相似文献   
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