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1.
This paper describes a problem-solving framework In which aspects of mathematical decision theory are incorporated into symbolic problem-solving techniques currently predominant in artificial intelligence. The utility function of decision theory IS used to reveal tradeoffs among competing strategies for achieving various goals, taking into account such factors as reliability, the complexity of steps in the strategy, and the value of the goal. The utility function on strategies can therefore be used as a guide when searching for good strategies. It is also used to formulate solutions to the problems of how to acquire a world model, how much planning effort is worthwhile, and whether verification tests should be performed. These techniques are illustrated by application to the classic monkey and bananas problem.  相似文献   

2.
Voice disorders, which may be caused by the stuttering problem, have been noted in at least one-third of stutterers seen. Basically, stutterers have false speech images that normal speech is perfect and without natural dysfluencies (repetitions, pauses, etc.). Many stutterers also have erroneous vocal images of how they should or should not sound. Both images control speech and voice. Clinical experience indicates that vocal rehabilitation should be used in conjunction with speech therapy for many stutterers.  相似文献   

3.
A general framework is presented for concept identification based on hypothesis-testing theory. It is a modification of the duoprocess theory presented by Chumbley (1972). It is shown how Markov models for various complex concept identification tasks may be derived from this framework and how such models may be analyzed by making use of probability generating functions. Two experiments are described. In experiment 1 three tasks were used: two simple tasks, where the subject either only had to select the relevant dimension in order to solve the problem or only had to learn a short list of paired-associates, and a more complex task, where both processes were needed to reach the solution. The results were in general favorable to the theory. Experiment 2 was designed to test the application of the theory to the four-choice concept problem. The predictions of the theory are compared to those of the subproblem learning theory of trabasso and Bower (1964), modified to include a ‘learning-on-errors’ assumption. The fit of the duoprocess theory was reasonably good and superior to that of the subproblem learning theory.  相似文献   

4.
G. E. Moore opined that the paradox of analysis might be avoided if it could be shown that sentences expressing conceptual analyses convey information not only about concepts, but also about the expressions they use. If so, "to be a brother is to be a male sibling" and "to be a brother is to be a brother" might express the same proposition, and yet not be identical in information value as the paradox suggests. How sentences might do this, Moore could not see. Many philosophers have pointed out an obvious way in which sentences might be said to convey information about the expressions they use. Some have suggested this information might be used to develop Moore's intuition and resolve the paradox of analysis. I argue that this approach fails. I present a version of the paradox of analysis that resists this sort of solution.  相似文献   

5.
短时记忆提取机制研究   总被引:5,自引:0,他引:5  
肖崇好  黄希庭 《心理科学》1999,22(4):302-304
该实验操作探测数字在记忆集中的位置来研究短时记忆的提取机制。结果发现:用Sternberg范式研究短时记忆提取机制存在缺限:操作记忆集不能反映被试的搜索过程。该研究显示:短时记忆的提取不是以自始至终或平行扫描为前提。短时记忆的提取机制受记忆集大小的影响较大。记忆集小于3时,短时记忆的提取是系列自中断扫描;记忆集大于3时,短时记忆的提取以记忆项目的痕迹强度为依据。  相似文献   

6.
The category theory concept of a commutative diagram is used to construct a model of the way in which symbolic processes are applied to problem solving. The model provides for a relationship between symbolic processes and the problem which depends on structural isomorphism and consistency, but is independent of similarity between symbol elements and problem elements. It is then shown that several different levels of thought can be distinguished within the basic model. More information is needed to assign symbolic processes to a problem in a consistent way with higher-level thought processes than with lower-level processes. These information-processing requirements permit the approximate age of mastery of each level to be predicted, thereby offering an alternate theory of cognitive developmental stages. Two experiments designed to test the theory are reported.  相似文献   

7.
During the course of pilot studies and two formal experiments examining the learned-helplessness phenomenon in rhesus monkeys, 5 subjects failed to escape in a shuttlebox following earlier experience with aversive stimulation in primate-restraining chairs. The present report details a therapeutic manipulation designed to reverse these subjects' maladaptive behavior in the shuttlebox. Introduction of a different fear stimulus (a net previously used to restrain the animals) was found to be effective in inducing shuttlebox escape and avoidance learning. The implications of the present findings for an understanding of the learned-helplessness phenomenon and their relevance to therapy for human depression are discussed.  相似文献   

8.
The respective efficiency of the cerebral hemispheres in processing visually presented vowels is discussed and examined in a tachistoscopic experiment with normal subjects. It is suggested that results from dichotic listening experiments cannot be used to predict performance on the same material in the visual modality. The physical characteristics of the stimulus, in both modalities, contribute to the pattern of hemispheric advantage and cannot be ignored in the interpretation of results from dichotic listening and tachistoscopic experiments.  相似文献   

9.
Previous studies of the identification of rotated symbols have been restricted to either alphanumeric characters or symbols designed to be similar in complexity and type to alphanumerics. These researches have found identification response times to be independent of the magnitude of a symbol's angular displacement from a standard upright position, such findings being typically interpreted as supporting a feature extraction model of identification. In the present experiment complex Japanese characters were used to assess whether such a feature extraction interpretation could be generalized to identifying complex rotated symbols. Identification response times were also found to be constant across all non-standard orientations of the characters, supporting a feature extraction interpretation, but quicker times for standard cases suggested that some qualifications might be necessary.  相似文献   

10.
SVIB profiles of 1169 freshmen entering a college of engineering were grouped according to total occupational scale profile similarity into 28 code types. Mean scores or percentages for the individuals in each code type were compared to base rate values for income variables including ability, personality, and socioeconomic data and outcome variables including academic progress, choice of major, counsel-seeking behavior, and place of residence. The data for four code types were presented together with examples of how the results might be used by a counselor. The investigators concluded that SVIB profile types can be useful in acting as moderator variables to predict student characteristics, and that total profile analysis of the SVIB occupational scale merits further attention.  相似文献   

11.
钟面画测试被广泛用于研究和测试老年人群中的各种认知缺陷和认知老化,是一种有用的筛选老年痴呆症病人的工具。近年来它也被用于研究正常儿童和ADHD儿童。该文回顾了钟面画测试所涉及的内部认知过程以及影响钟面画测试的各种因素、钟面画测试与执行功能测试之间的相关,并且重点回顾了钟面画测试在正常儿童和ADHD儿童中的研究。由于钟面画测试本身简便、快捷,可以迅速地大规模筛选障碍儿童,在这方面的研究具有重大的实践意义。  相似文献   

12.
The paper considers the issues, raised by Koriat et al. (1973), of the consistency and reliability of measures of habituation currently used in personality research. It is argued that the problem of reliability is not as serious as Koriat et al. proposed and that specificity of measures of habituation is a theoretical rather than a methodological problem. It is proposed that ambiguity in the literature on the personality correlates of habituation is more likely to be due to the failure to consider the effects of stimulus conditions on habituation than to the problems of reliability and specificity.  相似文献   

13.
A double reversal single-subject experimental design was used to study the effects of visual feedback on the hemispheric alpha asymmetries of a male subject during a linguistic task. Results indicated that the subject demonstrated flexibility in hemispheric alpha and corresponding processing strategies employed when an alpha biofeedback procedure was used. These results provide further support for the notion that right and left hemispheric activation is associated with different, yet compatible, cognitive strategies and that both can be manipulated under conditions of feedback.  相似文献   

14.
Over the course of psychology’s first several decades, the language used to convey the subject matter gradually shifted from being free and literary to being strictly constrained and disciplined by increasingly focused theoretical demands. The project described here, “Disciplining Psychology,” aimed to depict this transformation by generating images of the faces of three highly influential psychologists—William James, Sigmund Freud, and B. F. Skinner. Each image is composed of the words used in one of each individual’s most important books. The tightening of the disciplinary vocabulary is revealed in the differences among the three arrays of words themselves, but I have also striven to reflect it in the aesthetic aspects of each image. The method used here could easily be extended to a wider array of authors, texts, and psychological topics.  相似文献   

15.
Attentional biases and the right-ear effect in dichotic listening   总被引:2,自引:0,他引:2  
Most dichotic listening experiments permit subjects to deploy attention in any way they choose. We argue that this adds uncontrolled variance to the observed right-ear advantage. In the first experiment, more robust laterality effects were obtained in an identification task with focused than with divided attention. Such differences were not found in the second experiment, when a detection procedure was used. Virtually all the laterality effect observed in the second study could be attributed to subjects who were biased attenders, in the sense that they exhibited more intrusions from the right ear to the left than vice versa. However, rather than indicating that laterality effects are simply attentional bias, this effect can be attributed to an asymmetry of perceptual discrimination.  相似文献   

16.
The hypothesis that latent inhibition could be reduced by extinguishing the experimental context, that is, exposing the rats to the context between exposure to the conditional stimulus (CS) and conditioning, was tested. All experiments used the conditioned emotional response procedure. In Experiment 1, extinction was not effective when the animals were exposed to the clicker 40 times off the baseline of responding for food and when the clicker CS was partially reinforced with shocks during the test phase. In Experiments 2 and 3, latent inhibition could be reduced by extinction if the animals were exposed to the CS 24 or 16 times on-baseline, and if continuous reinforcement was used during the test. In Experiments 4, 5, and 6, we attempted to determine which variable was responsible for the discrepant results. In Experiment 4, extinction was effective with 20 or 40 on-baseline exposures to the CS, using continuous reinforcement during the test. In Experiment 5, extinction was not effective with exposure on- or off-baseline, using 24 exposures and partial reinforcement. Finally, in Experiment 6, extinction reduced latent inhibition using continuous, but not partial, reinforcement with 40 exposures off-baseline. From these results, we concluded that Wagner's model of habituation was not sufficient to account for latent inhibition and that a hybrid model, using both associative and cognitive representational processes, was necessary.  相似文献   

17.
Allocentric tendencies were studied with a multimethod questionnaire and Illinois undergraduates. Nine scales measuring different aspects of allocentrism were shown to have good reliability and to be intercorrelated, thus showing convergent validity. Factor analysis identified three aspects: subordination of personal to group goals, the ingroup as extension of the self, and ingroup identity. The scales also had satisfactory discriminant validity. Those high on idiocentric tendencies used equity and those high in allocentric tendencies used equality and need in distributing rewards. A second study found that those who are allocentric are more likely to emphasize the values of cooperation, equality, and honesty, and those who are idiocentric to emphasize the values of comfortable life, competition, pleasure, and social recognition. Those who were allocentric reported receiving more social support and a better quality of social support; those who were idiocentric were higher in achievement motivation, alienation, anomie, and reported greater loneliness.  相似文献   

18.
In two conditioned suppression experiments, rats received Pavlovian forward defense conditioning in which tonal conditioned stimuli (CSs) terminated with the onset of scrambled grid shock unconditioned stimuli (USs). After this experience, the rats then received a Pavlovian backward conditioning procedure in which the same USs now terminated with the onset of the same CSs. Although the two experiments differed greatly in terms of CS and US parameters, number of forward and backward pairings, and in terms of the general techniques used to establish and measure the Pavlovian conditioned response (CR), the results of both experiments agreed in showing that backward conditioning can indeed weaken a CR based on forward pairings. The results also show that, under some conditions, the backward procedure can be at least as effective in weakening an established CR as the traditional CS-alone extinction procedure; but, under other conditions, the backward procedure is less effective and leads to more spontaneous recovery than the CS-alone procedure.  相似文献   

19.
差数显著性t检验与元分析方法的模拟对比   总被引:2,自引:0,他引:2  
利用计算机程序构造被试总体、模拟实验研究程序进行抽样研究 ,探讨差数显著性t检验方法与元分析方法在检验实验结果数据和进行实际应用方面的差异。模拟实验结果表明 ,差数显著性t检验与总体效果大小和样本容量有明显关系 ,但与随机抽样分布样本数目基本无关 ;抽样分布样本效果大小的平均值可以作为总体效果大小的估计值 ,它与样本容量和抽样样本数目有密切关系 ;本研究提供的实际应用数据结果可以作为研究者进行元分析方法实验研究的参考依据  相似文献   

20.
A left-handed woman developed visual object agnosia, prosopagnosia, and visual disorientation after resection of the right occipital lobe. Color agnosia and alexia were absent. When asked to identify objects presented visually, the patient's errors represented visually related objects (underspecifications) or perseverations. Identification was facilitated when she observed the object being used in a natural way. Identification was impaired by surrounding the object with unrelated objects, decreasing the background illumination, decreasing the duration of exposure of the object to the patient, and probably also by decreasing the visual angle subtended by the object. In addition, there were disturbances of visualization (i.e., imaging in the absence of a visual stimulus) that paralleled the perceptual difficulties. We conclude that: (1) A deficit in visual perception, characterized by insufficient feature analysis of visual stimuli, was the basis of the visual agnosia in this case. (2) The visual agnosia could not be explained by (a) a vision-language disconnection syndrome, (b) decay of visual memory traces, or (c) deficiencies in the visual fields (pathologic Funktionswandel). (3) The ability to visualize (visual imagery) probably utilizes some of the same neural pathways used in perception. (4) The results in this case probably can be generalized to some but not all cases of visual agnosia; in particular, the deficit in most previously reported patients with prosopagnosia is similar to that of our case. However, agnosic alexia and color agnosia usually have a different neuropsychological basis.  相似文献   

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