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991.
Three social-interaction behaviors of a withdrawn, chronic schizophrenic were increased using a discriminated avoidance (“nagging”) procedure. The three behaviors were: (a) voice volume loud enough so that two-thirds of his speech was intelligible at a distance of 3 m; (b) duration of speech of at least 15 sec; (c) placement of hands and elbows on the armrests of the chair in which he was sitting. “Nagging” consisted of verbal prompts to improve performance when the behaviors did not meet their criteria. A combined withdrawal and multiple-baseline design was used to evaluate the effectiveness of the procedure, and the contingency was sequentially applied to each of the three behaviors in each of four different interactions to determine the degree of stimulus and response generalization. Results indicated that the contingency was the effective element in increasing the patient's appropriate performance, and that there was a high degree of stimulus generalization and a moderate degree of response generalization. After the patient's discharge from the hospital, the durability of improvement across time and setting was determined in followup sessions conducted at a day treatment center and at a residential care home. Volume and duration generalized well to the new settings, while arm placement extinguished immediately.  相似文献   
992.
Attenuation of conditioned suppression during intracranial stimulation was compared with that during food reinforcement. Response rates controlled by food and by brain stimulation were equalized on a multiple schedule by adjusting the stimulating current. When foot shock was delivered during timeout periods separating response components, responding for food was significantly more suppressed than responding for brain stimulation. When components were shortened from 10 to 2 minutes, responding maintained by either food or brain stimulation showed a similar temporal pattern of suppression preceding each shock, but responding in the component involving food remained significantly more suppressed. Explanations for the attenuated suppression during brain stimulation based on neural disruption, stimulus blocking, and analgesic properties were questioned. The increased responding during brain stimulation seemed to reflect greater response strength relative to food reinforced responding.  相似文献   
993.
College students were instructed to press a button for points under a single reinforcement schedule or under a variety of reinforcement schedules. Instructions for a single schedule were either specific or minimal. Instructions on a variety of schedules involved specific instructions on eight different schedules of reinforcement. Subsequent to the varied training, responding under a fixed-interval schedule occurred at a low rate. Both the minimal and specific instruction training led to fixed-interval responding that was similar to the responding exhibited during training. These findings suggest that under certain conditions instructed behavior is sensitive to changes in contingencies.  相似文献   
994.
Items bundles     
An item bundle is a small group of multiple choice items that share a common reading passage or graph, or a small group of matching items that share distractors. Item bundles are easily identified by paging through a copy of a test. Bundled items may violate the latent conditional independence assumption of unidimensional item response theory (IRT), but such a violation would not typically suggest the existence of a new fundamental human ability to read one specific reading passage or to interpret one specific graph. It is important, therefore, to have theoretical concepts and empirical checks that distinguish between, on the one hand, anticipated violations of latent conditional independence within item bundles, and, on the other hand, violations that cannot be attributed to idiosyncratic features of test format and instead suggest departures from unidimensionalty. To this end, two theorems on unidimensional IRT are extended to describe observable item response distributions when there is conditional independencebetween but not necessarilywithin item bundles.The author is grateful to Ivo Molenaar and the referees for many helpful suggestions, and to D. Thayer for assistance with computing.  相似文献   
995.
Stokes, Osnes, and Guevremont's (1987) implicit definition of correspondence classes appears close to ours (Matthews, Shimoff, & Catania, 1987). Their definition, however, is fundamentally procedural and thus may have to be modified as experimental methodologies are refined. The advantage of our contingency-space analysis is that it is independent of specific procedures and focuses attention on problems inherent in some procedural definitions. Specifically, a contingency-space analysis addresses the issue of distinguishing specific instances from classes and reminds us that correspondence can be identified as a class only on the basis of observing a population of opportunities for say/do sequences in which the subject sometimes does not say.  相似文献   
996.
997.
During Phase I, three female human subjects pressed a button for monetary reinforcement in two-component concurrent variable-interval schedules. Five different reinforcement frequencies were used in component A, whereas the reinforcement frequency in component B was held constant. Absolute rates of responding conformed to equations proposed by Herrnstein to describe concurent performances, and the ratios of the response rates and the times spent in the two components conformed to the matching law. During Phase II, the availability of reinforcement in component A was signaled by the illumination of a lamp. This resulted in suppression of response rates in component A and elevation of response rates in component B, these changes being reflected in a distortion of the matching relationship which took the form of a bias in favor of component B.  相似文献   
998.
Matching models in the analysis of cross-classifications   总被引:1,自引:0,他引:1  
Inference models motivated by the combinatorial chance literature and the concept of object matching may be used in the analysis of a contingency table if the conditional assumption of fixed row and column totals is imposed. More specifically, by developing a matching reinterpretation for several problems of interest in the prediction analysis of cross-classifications—as defined by Hildebrand, Laing and Rosenthal, appropriate significance tests can be given that may differ from those justified by the more common multinomial models. In the course of the paper the distinction between a degree-1 statistic (based on the relationship between single objects) and a degree-2 statistic (based on the relationship between object pairs) is reviewed in some detail. Also, several specializations are presented to topics of current methodological importance in psychology; for instance, a number of references are made to the measurement of nominal scale response agreement between two raters.Partial support for this research was provided by the National Science Foundation through GSOC-77-28227.  相似文献   
999.
A SURVEY OF LOST AND FOUND CLASSIFIED SECTIONS IN METROPOLITAN AND SMALLER NEWSPAPERS REVEALED DISPARATE RATES BETWEEN LOST ADS AND FOUND ADS: Lost ads greatly outnumbered Found ads, probably because newspapers usually require the finders of lost personal property to pay for Found advertisements. The effect of a Free-Found-Ad policy on the rate of Found advertisements placed in the Lost and Found sections of three community newspapers was investigated using a multiple-baseline design. The results suggested that the Free-Found-Ad policy was effective in increasing the rates of Found ads in all three newspapers. To determine whether increases in Found ads resulted in increases in recovered property, a sample of individuals who placed Found ads were surveyed in both baseline and treatment conditions and asked if the found items had been claimed by their owners. The Free-Found-Ad policy appeared to be effective in increasing the amount of personal property returned. The study concluded that community newspapers can provide incentives to increase such help-giving or altruistic behaviors. The implications of this study for a general policy-research strategy are discussed.  相似文献   
1000.
Memory for sequences of stimuli and responses   总被引:3,自引:3,他引:0       下载免费PDF全文
Two experiments sought to determine if pigeons could discriminate and remember recent sequences of stimuli and responses. A variant of Konorski's short-term memory procedure involving successive presentation of sample and test stimuli was used. The samples were stimulus-response pairs of the form, (S-R)1–(S-R)2. Differential test responding disclosed memory of the two-item samples, with birds showing earlier and greater control by the second item than the first (Experiment 1). When the retention interval separating the second item of the sample sequence from the test stimulus was lenghtened from .5 to 2.0 or 4.0 sec, a systematic loss of stimulus control resulted; however, when varied over the same temporal range, the interval between the two items of the sample sequence had a much smaller effect, or none at all (Experiment 2). These results support an account of response-sequence differentiation that stresses short-term memory of organized behavior patterns.  相似文献   
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