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1.
A story understander needs a great deal of knowledge about people's goals. This knowledge is needed to infer explanations for the behavior of the characters in a story. Sometimes a character's behavior cannot be explained in terms of a particular goal, but only in relation to a set of recurring goals that a character anticipates having. The concept of goal subsumption is introduced to deal with these situations. Goal subsumption is a way of planning for many goals at the same time. It occurs in three different types of story situations, each of which has its own rules for recognition and understanding.  相似文献   

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3.
It is shown that deterministic models can compete effectively with stochastic models in summarizing concept identification behavior. Three groups of deterministic models are examined. Examination of individual learners' trial by trial behavior in a concept experiment shows: (1) One person exhibited behavior consistent with a Hypothesis Permutation (HP) model despite being a nonlearner who showed no evidence of improvement over a period of 24 trials. However, when all 50 persons studied in each of two treatment groups were examined, only 22 members of one group and 10 of the other showed no inconsistencies with deterministic local consistency assumptions. (2) Certain deterministic computer programs could find at least one satisfactory order for predicting all responses by 18 of the 22 consistent solvers and 6 of the 10 consistent solvers, respectively, in the two groups just mentioned. For these 24 persons, then, a less restrictive deterministic model is adequate than for the others. (3) Those 38 original members of the first treatment group who met a stringent learning criterion were compared with respect to predictions generated by stochastic and mathematized deterministic models. One deterministic model (RSS-U 9-state) is in some respects the best of the models examined, but this success is a partial reflection of estimating eight parameters from the data.  相似文献   

4.
Family resemblances: Studies in the internal structure of categories   总被引:2,自引:0,他引:2  
Six experiments explored the hypothesis that the members of categories which are considered most prototypical are those with most attributes in common with other members of the category and least attributes in common with other categories. In probabilistic terms, the hypothesis is that prototypicality is a function of the total cue validity of the attributes of items. In Experiments 1 and 3, subjects listed attributes for members of semantic categories which had been previously rated for degree of prototypicality. High positive correlations were obtained between those ratings and the extent of distribution of an item's attributes among the other items of the category. In Experiments 2 and 4, subjects listed superordinates of category members and listed attributes of members of contrasting categories. Negative correlations were obtained between prototypicality and superordinates other than the category in question and between prototypicality and an item's possession of attributes possessed by members of contrasting categories. Experiments 5 and 6 used artificial categories and showed that family resemblance within categories and lack of overlap of elements with contrasting categories were correlated with ease of learning, reaction time in identifying an item after learning, and rating of prototypicality of an item. It is argued that family resemblance offers an alternative to criterial features in defining categories.  相似文献   

5.
Basic objects in natural categories   总被引:1,自引:0,他引:1  
Categorizations which humans make of the concrete world are not arbitrary but highly determined. In taxonomies of concrete objects, there is one level of abstraction at which the most basic category cuts are made. Basic categories are those which carry the most information, possess the highest category cue validity, and are, thus, the most differentiated from one another. The four experiments of Part I define basic objects by demonstrating that in taxonomies of common concrete nouns in English based on class inclusion, basic objects are the most inclusive categories whose members: (a) possess significant numbers of attributes in common, (b) have motor programs which are similar to one another, (c) have similar shapes, and (d) can be identified from averaged shapes of members of the class. The eight experiments of Part II explore implications of the structure of categories. Basic objects are shown to be the most inclusive categories for which a concrete image of the category as a whole can be formed, to be the first categorizations made during perception of the environment, to be the earliest categories sorted and earliest named by children, and to be the categories most codable, most coded, and most necessary in language.  相似文献   

6.
Cognitive reference points   总被引:1,自引:0,他引:1  
Two methods were used to test the hypothesis that natural categories (such as colors, line orientations, and numbers) have reference point stimuli (such as focal colors, vertical and horizontal lines, and numbers that are multiples of 10) in relation to which other stimuli of the category are judged. In Experiment I, subjects placed pairs of stimuli into sentence frames consisting of linguistic “hedges” such as “— is essentially—.” Results were that the supposed reference stimuli were most often placed in the second (reference) slot. In Experiment II, the subject placed a stimulus in physical space to represent his feeling of the psychological distance of that stimulus from another spatially fixed stimulus. Results showed that, when supposed reference stimuli were fixed, other stimuli were placed closer to them than vice versa. The results have substantive implications for the understanding of internal structure of categories and methodological implications for the mapping of reference points, quantification of linguistic intuitions, and the assumption of symmetry in psychological distance judgments.  相似文献   

7.
Triads of occupations were given to 1300 high-school pupils of both sexes in order to find the affinities of the occupations and the values they used to arrive at the affinities. The values used to perceive occupations come from the subject; nevertheless they could be categorized into a scheme of 20 different values, with the residue category containing less than 1% of the answers. In accordance with previous research in this field, an almost universal structure of occupations was found. The following variables had no influence on the choice of occupational affinities: age, trend of study, SES, father's occupation, mother's occupation, vocational maturity, and preferred occupation. Only the pupils of one school were significantly different in affiliating the occupations in the triads. Furthermore, girls perceive the world of occupations more uniformly than boys.Underlying this universal structure of occupations there exists a latent structure, specific to each individual, which explains why the world of occupations is seen in the way it is. This latent structure of occupations is influenced by the individual's specific background.  相似文献   

8.
An anatomical and behavioral review of 29 reported cases of corpus callosum agenesis is presented. This review addresses itself to two questions: (1) Do acallosals manifest split-brain symptoms? (2) Is the corpus callosum necessary for the establishment of lateralization? Unlike the commissurotomy cases, acallosals show few symptoms of hemispheric disconnection. Behavioral strategies, use of noncallosal commissures, elaboration of ipsilateral pathways, and bilateral representation of function are discussed and evaluated as possible mechanisms of compensation. An impairment in spatiomotor functioning often accompanies callosal agenesis. Results of acallosal lateralization testing are examined and problems in interpretation are discussed. Current evidence does not conclusively establish that the corpus callosum is needed for lateralized development of some functions. However, the corpus callosum may play a role in the satisfactory performance of “lateralized” (i.e., spatial, linguistic) functions.  相似文献   

9.
A polar-coordinate analogue of Fourier synthesis generates organic-appearing “free forms” that can be continuously deformed along any desired number of difficult-to-verbalize dimensions. Since the dimensions are also circular, the forms correspond to points on the surface of a torus which, though conveniently finite, is free of bounding edges. Two experiments explore a particular two-dimensional set of 81 such forms. The first shows that perceived pair-wise similarities among the individual forms are well explained purely in terms of the distances among their corresponding points in the toroidal parameter space. The second, however, establishes that forms that tend to be grouped together as having the same cognitive interpretation define regions in parameter space that are variously shaped or even bimodal and, hence, that cannot be explained solely on the basis of the fixed set of pair-wise similarities. The stimuli appear to offer a novel combination of cognitive richness and low-dimensional parametric control.  相似文献   

10.
Measurements derived from reaction time (RT), movement time (MT), and an index of neural adaptability (NA) derived from averaged evoked potentials are significantly related to each other as well as to g factor scores extracted from a battery of 15 psychometric tests in a sample of 54 severely retarded adults. The RT-MT and NA variables show a shrunken multiple R of .64 (p < .001) with psychometric g.  相似文献   

11.
Recent work reporting neonatal auditory responses to complex tones generated by applying electrical square-wave stimuli to loudspeakers is reviewed with reference to the nature of the acoustic stimulus. Attention is particularly drawn to the harmonic structure of such tones in relation to the nonlinear frequency response of small loudspeakers. A 13-octave band analysis of some “square-wave tones” is given to illustrate the difficulties of interpreting the results of work using such complex stimuli. The findings of the previous studies are ascribed essentially to differences in the stimulus bandwidth, rather than to differences in audiofrequency, and difficulties apparently generated by using differences in stimulus bandwidth as the sole explanation are at least partially resolved.  相似文献   

12.
A series of three experiments was conducted to verify the hypothesis that age differences in paired-associate learning proficiency across adolescence stem from the development of increasing elaborative propensity. An auxiliary aim was to determine whether previous study-to-study discrepancies in the pertinent age functions should be attributed to corresponding variations in learning materials or in characteristics of the populations sampled. Taken together, the results of the experiments provided support for the hypothesis. They also indicated, however, that students in late adolescence vary markedly in elaborative propensity, to the point that a substantial proportion of them are hardly distinguishable from preadolescents.  相似文献   

13.
The study investigated the effects of expectations upon task performance in a simulated work environment. In a 2 × 2 factorial design, individuals of high and low self-esteem responded to either a favorable or unfavorable expectation. It was found that only high self-esteem individuals differed significantly in their response to the expectation manipulation. The results were discussed relative to self-consistency formulations and implications for organizational behavior were suggested.  相似文献   

14.
The Basic Interest Scales (BIS) and the Occupational Scales (O-S) of the revised Strong Vocational Interest Blank for Women (TW 398) were assigned Holland codes, and component scores for the BIS and O-S were separately developed, intercorrelated, and evaluated along with standardized composite scores representing each of the 11 O-S Groups on the profile. The dimensionality of the BIS and O-S was similar, and similar in number to Holland's theory, but the components were only partially congruent. Some profile Groups provided relatively good representations of BIS and/or Occupational scale components, and the grouping of the O-S provided important information not otherwise readily available. Holland's dimensions are not uniformly represented in either the BIS or O-S, and despite some similarities, fundamental problems of compatibility appeared to exist in relating the structure of this instrument to Holland's formulations. Women's interests are in need of independent study.  相似文献   

15.
16.
Learning from experience involves three distinct components—generating behavior, assigning credit, and modifying behavior. We discuss these components in the context of learning search heuristics, along with the types of learning that can occur. We then focus on SAGE, a system that improves its search strategies with practice. The program is implemented as a production system, and learns by creating and strengthening rules for proposing moves. SAGE incorporates five different heuristics for assigning credit and blame, and employs a discrimination process to direct its search through the space of rules. The system has shown its generality by learning heuristics for directing search in six different task domains. In addition to improving its search behavior on practice problems, SAGE is able to transfer its expertise to scaled-up versions of a task, and in one case, transfers its acquired search strategy to problems with different initial and goal states.  相似文献   

17.
Four experiments utilizing tachistoscopic presentation of verbal and spatial stimuli to visual half-fields are presented. Three experiments failed to find any cerebral lateralization effect of the type predicted from existing models of cerebral lateralization processes. One experiment found marked lateralization effects. Since the experiments differ only in the ratio of trials to experimental stimuli, it is argued that cerebral lateralization experiments are detecting only a memory process occurring after subjects have learned all the stimuli to be presented. When new stimuli are presented on each trial, no cerebral lateralization effects are found, suggesting that active ongoing cognitive processing is independent of lateralization.  相似文献   

18.
Speech communities in the British West Indies typically include two major dialect or code distinctions: (1) a standard variety of British West Indian English, and (2) a local variety of English-based dialect. Each dialect or code is intimately linked with political, social, racial, and economic class distinctions. In bicultural settings, characterized by diglossia, there are special situations in which loyalty to one's mother tongue conflicts with social, economic, and political expediency. “No win” speech events or contests, the product of conflicting sociocultural values, become salient features of this particular kind of bicultural setting. A comparatively high incidence of teacher-reported stammering found in two British West Indian speech communities supports this notion and suggests that stress, originating at a sociocultural level, is symbolically expressed through attitudes toward and usages of language. These results further suggest that the classroom, now a “battleground”, will suffer as an effective teaching/learning environment. This paper presents arguments for the teaching of Standard English as a second language with an emphasis on giving regional dialects appropriate and long overdue recognition.  相似文献   

19.
A review is presented of a number of recent results concerning fundamental measurement structures with a particular emphasis on generalizations of physical measurement. Relational structures are classified in terms of richness and redundancy of their automorphism groups (i.e., in terms of their symmetries). By means of this classification, the possible types of measurement scales are described, and the possibilities for structures with concatenation operations (either associative or nonassociative and either positive or intensive) and for conjoint structures whose automorphisms factor into component automorphisms are explicitly spelled out. Certain conjoint structures with concatenation operations on components are viewed as generalizations of classical physical measurement and some of their most important algebraic and representational properties are explored.  相似文献   

20.
The mature visual system possesses mechanisms that analyze visual inputs into bands of spatial frequency. This analysis appears to be important to several visual capabilities. We have investigated the development of these spatial-frequency channels in young infants. Experiment 1 used a masking paradigm to test 6-week-olds, 12-week-olds, and adults. The detectability of sine wave gratings of different spatial frequencies was measured in the presence and the absence of a narrowband noise masker. The 12-week data showed that at least two spatial-frequency channels with adultlike specificity are present at 12 weeks. The 6-week data did not reveal the presence of narrowband spatial-frequency channels. Experiment 2 used a different paradigm to investigate the same issue. The detectability of gratings composed of two sine wave components was measured in 6-week-olds and adults. The results were entirely consistent with those of experiment 1. The 12-week and adult data indicated the presence of narrowband spatial-frequency channels. The 6-week data did not. The results of these experiments suggest that the manner in which pattern information is processed changes fundamentally between 6 and 12 weeks of age.  相似文献   

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