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941.
942.
It is argued that the manner in which we teach science in the high schools represents an outdated positivistic conception of science. The standard presentation of a year of each of chemistry, biology and physics should be replaced by an integrated science plus history, philosophy, and sociology of science which would take a total of three years to complete. A proper appreciation for the true nature of science is essential to the continued health of the scientific enterprise.  相似文献   
943.
This paper tests psychologists' frequent assumption that dictionaries are psychologically realistic models of polysemy in the mental lexicon. Psychologists have not often explored the nature of polysemy, and lexicographers' methods have not involved scientific sampling of usages or informants. It is argued, however, that the lexicographic technique of citation sorting is an effective way of discovering sense differences. Here this technique was used in three tasks involving usage samples for 24 high- and low-frequency nouns varying widely in degree of polysemy in the dictionary. Analyses of agreement within and between subjects showed that subjects consistently judged and substantially agreed upon the major senses of most nouns, but that few nouns in either frequency group were perceived to have more than three significant senses. Additionally, the possibility that larger usage samples will bias people to make more sense groupings was found not to be true, suggesting that the larger number of senses lexicographers create for high-frequency words are not artifacts of larger usage samples.This research was partially supported by grants from the Spencer and Sloan Foundations to George A. Miller.  相似文献   
944.
Seventy-six undergraduates were given the titles and first lines of Beatles' songs and asked to recall the songs. Seven hundred and four different undergraduates were cued with one line from each of 25 Beatles' songs and asked to recall the title. The probability of recalling a line was best predicted by the number of times a line was repeated in the song and how early the line first appeared in the song. The probability of cuing to the title was best predicted by whether the line shared words with the title. Although the subjects recalled only 21% of the lines, there were very few errors in recall, and the errors rarely violated the rhythmic, poetic, or thematic constraints of the songs. Acting together, these constraints can account for the near verbatim recall observed. Fourteen subjects, who transcribed one song, made fewer and different errors than the subjects who had recalled the song, indicating that the errors in recall were not primarily the result of errors in encoding.  相似文献   
945.
The purpose of this study was to examine the predictive validity of a teacher nomination procedure for identifying at- risk children. Two hundred and twenty-five children were nominated by their teachers as well- adjusted (n= 75), socially withdrawn (n=76), or socially aggressive (n=74) during the fourth grade. Five years later, 198 of these children (88%) were located and their adjustment evaluated. Significant differences among the nominated children were found on a variety of measures, including academic grades, sociometric status, and social behavior. In addition, differences in school dropout and delinquent offenses were noted. Results are discussed in terms of the validity of teacher nomination procedures and their utility in identifying at- risk youth.  相似文献   
946.
This study explored a number of temporal (durational) parameters of consonant and vowel production in order to determine whether the speech production impairments of aphasics are the result of the same or different underlying mechanisms and in particular whether they implicate deficits that are primarily phonetic or phonological in nature. Detailed analyses of CT scan lesion data were also conducted to explore whether more specific neuroanatomical correlations could be made with speech production deficits. A series of acoustic analyses were conducted including voice-onset time, intrinsic and contrastive fricative duration, and intrinsic and contrastive vowel duration as produced by Broca's aphasics with anterior lesions (A patients), nonfluent aphasics with anterior and posterior lesions (AP patients), and fluent aphasics with posterior lesions (P patients). The constellation of impairments for the anterior aphasics including both the A and AP patients suggests that their disorder primarily reflects an inability to implement particular types of articulatory gestures or articulatory parameters rather than an inability to implement particular phonetic features. They display impairments in the implementation of laryngeal gestures for both consonant and vowel production. These patterns seem to relate to particular anatomical sites involving Broca's area, the anterior limb of the internal capsule, and the lowest motor cortex areas for larynx and tongue. The posterior patients also show evidence of subtle phonetic impairments suggesting that the neural instantiation of speech may require more extensive involvement, including the perisylvian area, than previously suggested.  相似文献   
947.
Previous research has tentatively indicated that coercive, ineffective parenting might have a mediating role in the differential impact of marital discord on boys and girls. To further explore this role, we examined the relationship between children's perceptions of marital discord and their evaluations of parental discipline techniques. Ninety-one children aged 8 to 13 years (mean age: 11 years 4 months) were split into high, moderate, and low perceived marital discord on the basis of their responses to the Children's Perceptions Questionnaire (Emery & O'Leary, 1982). The children rated how coercive they believed both mothers and fathers would and should be in three discipline situations. Children with high marital discord indicated that both mothers and fathers would and should use more coercive behavior than did children with low marital discord. The effects of marital discord were stronger for boys than for girls. All children also believed that fathers would and should be more coercive than mothers. Results are discussed in relation to the effects of marital discord on children's social development with regard to sex of the child.Thanks are due to Mike Siegal and Pat Noller for their helpful comments on previous drafts.  相似文献   
948.
Transparent layer constancy   总被引:1,自引:0,他引:1  
Perceived transparency was studied as a constancy problem. In the episcotister (E-) model of scission, luminances are partitioned into layer and background components; four luminances determine values of two layer parameters that specify constancy of a transparent layer on different backgrounds. The E-model was tested in an experiment in which 12 Ss matched 24 pairs of four-luminance patterns by adjusting two luminances of the comparison pattern. Both the standard and the comparison were perceived as a transparent layer on a checkerboard. The E-model predicts matches when layer values are identical in the two patterns. One parameter was constant, constraining the adjustment along the second dimension. Obtained values corresponded well with E-predictions. Alternative models based on local luminance or average contrast ratios accounted for less variability. Results indicate that transparency models should utilize luminance, not reflectance, as the independent variable.  相似文献   
949.
Judgments of the color and shape of a stimulus specified by a cue indicating its location demonstrate stochastic independence. Evidence for the independence of color and orientation was obtained when the cue followed stimulus offset immediately, the cue followed stimulus offset by 2 s, and when either a central or peripheral precue focused attention on the cued stimulus at the time of its presentation. It appears that an object's color and orientation are represented independently even following the attentional focusing thought to support feature integration.  相似文献   
950.
Modification of Restle's theory (1970) explains the moon illusion and related phenomena on the basis of three principles: (1) The apparent sizes of objects are their perceived visual angles. (2) The apparent size of the moon is determined by the ratio of the angular extent of the moon relative to the extents subtended by objects composing the surrounding context, such as the sky and things on the ground. (3) The visual extents subtended by common objects of a constant physical size decrease systematically with increasing distance from the observer. Further development of this theory requires specification of both the components of the surrounding context and their relative importance in determining the apparent size and distance of the moon.  相似文献   
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