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831.
This study investigated the relationships among family environment, demographic measures, the decisions made by unintentionally pregnant adolescents regarding postdelivery plans and the certainty with which these decisions were made. Subjects were 175 pregnant adolescents, ages 14 through 22, who intended to carry their pregnancies to term. Greater uncertainty was associated with living with both natural parents or with mother only. Higher levels of negative affect were related to lower levels of perceived family cohesion, independence, expressiveness, and intellectual-cultural orientation. Age, trimester of pregnancy, and family constellation also were related to levels of negative affect. Discriminant analysis revealed that subjects choosing adoption were more likely to be older and to be white than were those choosing to keep the child. They also tended to perceive higher levels of expressiveness and independence in their families. The implications of these findings for the delivery of services and for future research efforts in this area are discussed. 相似文献
832.
Critical period effects in second language learning: the influence of maturational state on the acquisition of English as a second language 总被引:31,自引:0,他引:31
Lenneberg (1967) hypothesized that language could be acquired only within a critical period, extending from early infancy until puberty. In its basic form, the critical period hypothesis need only have consequences for first language acquisition. Nevertheless, it is essential to our understanding of the nature of the hypothesized critical period to determine whether or not it extends as well to second language acquisition. If so, it should be the case that young children are better second language learners than adults and should consequently reach higher levels of final proficiency in the second language. This prediction was tested by comparing the English proficiency attained by 46 native Korean or Chinese speakers who had arrived in the United States between the ages of 3 and 39, and who had lived in the United States between 3 and 26 years by the time of testing. These subjects were tested on a wide variety of structures of English grammar, using a grammaticality judgment task. Both correlational and t-test analyses demonstrated a clear and strong advantage for earlier arrivals over the later arrivals. Test performance was linearly related to age of arrival up to puberty; after puberty, performance was low but highly variable and unrelated to age of arrival. This age effect was shown not to be an inadvertent result of differences in amount of experience with English, motivation, self-consciousness, or American identification. The effect also appeared on every grammatical structure tested, although the structures varied markedly in the degree to which they were well mastered by later learners. The results support the conclusion that a critical period for language acquisition extends its effects to second language acquisition. 相似文献
833.
834.
Mark Johnson 《Journal of psycholinguistic research》1989,18(1):105-128
Hypothesising that the human parser is a specialized deductive device in which Universal Grammar and parameter settings are represented as axioms provides a model of how knowledge of language can be put to use. The approach is explained via a series of model deductive parsers for Government and Binding Theory, all of which use the same knowledge of language (i.e., underlying axiom system) but differ as to how they put this knowledge to use (i.e., they use different inference control strategies). They differ from most other GB parsers in that the axiom system directly reflects the modular structure of GB theory and makes full use of the multiple levels of reprepresentation posited in GB theory. 相似文献
835.
A very low-cost, high-throughput laboratory data acquisition and experiment control system may be configured by using a star network architecture with a low-cost microcomputer as network controller and one or more microprocessor-based single-board controllers as satellites. A network of this type, using Apple II microcomputer ($1,500 with 48K RAM and one minidiskette drive) as main node and up to seven KIM-1 microcontrollers ($159 each) as satellites is described, and its development is discussed in detail. 相似文献
836.
Goldstein, Rennick, Welch, and Shelly (1973) developed a visual searching task (VST) that succeeded in obtaining a hit rate of 94.1% correct classifications when comparing brain-damaged and normal subjects and a 79.4% hit rate when comparing brain-damaged and psychiatric subjects. Goldstein and Kyc (1978) reported 92.5% correct classifications for the brain-damaged vs. normal comparisons and 82.5% correct classifications for brain-damaged vs. schizophrenic comparisons. We computerized the administration of the VST and found 85.7% correct classifications for the brain-damaged vs. normal groups and 71.4% correct classifications for the brain-damaged vs. psychiatric group. These results suggest that the computerized VST (CVST) is also a potentially valid indicator of brain damage. 相似文献
837.
A review of pertinent recent events in psychological assessment suggests greater use of computerized testing systems in the future. Just as there are problems of response bias with paper-and-pencil test methods, there are also such problems when using the computer medium for assessment. Problem areas and possible solutions are reviewed. Future research needs are discussed. 相似文献
838.
Multimethod study of clinical judgment 总被引:1,自引:0,他引:1
Johnson PE Hassebrock F Duran AS Moller JH 《Organizational behavior and human performance》1982,30(2):201-230
Expert and novice clinicians judged the likelihood of disease alternatives and gave thinking-aloud protocols as they evaluated simulated cases of congenital heart disease. Specific combinations of cues in the patient data were manipulated to create alternate versions of a single case so that the use of critical cues could be identified. Analyses of variance of subjects' disease judgments revealed differences between expert and novice clinicians in their use of critical cues and cue combinations. Analyses of the thinking-aloud protocols revealed that clinicians with different degrees of expertise employed different interpretations of patient data cues as well as qualitatively distinct "lines of reasoning" in reaching clinical judgments. 相似文献
839.
840.