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981.
Two areas of research were explored in this meta-analysis: comparison of inductive versus deductive teaching approachs, and the use of advance organizers. This study involved the coding of 128 characteristics for 39 studies which spanned the period from 1957 through 1980. The coding variables included 57 which were concerned with features of the treatment while 12 were concerned with outcome attributes. Aspects such as research methodology, sample characteristics, and instructional experiences were examined quantitatively in terms of their relationships to the treatment effects through the use of a common metric for all studies. Mean effect sizes were calculated and reported.  相似文献   
982.
Undergraduate students who major in science make diverse career choices. Two such career choices are medical technologists and science teachers. One possible reason for science majors selecting different career choices might be attributed to varied personality dimensions. The purpose of this study was to identify a set of personality attributes that distinguish practicing medical technologists from practicing science teachers. The subjects of this study consisted of 83 medical technologists and 57 science teachers. Eysenck Personality (EPI) was utilized to investigate the personality attributes of subjects in terms of Eysenck's personality variable of Extroversion-Introversion and Neuroticism-Stability. Vocational Preference Inventory was utilized to investigate the vocational personality profile of subjects in terms of Holland's classification of occupations and work environment. Data with EPI revealed that there was no significant difference between medical technologists and science teachers with respect to Eysenck's personality variable of extroversion. However, there was found a significant difference between the two groups with respect to Eysenck's personality variable of neuroticism. Data with VPI revealed that there was no significant difference between medical technologists and science teachers with respect to Eysenck's personality variable of extroversion. Both the groups were characterized by the personality profile of IAS (Intellectual-Artistic-Social). This profile was different from that required earlier in literature.  相似文献   
983.
Over the years, professionals have hypothesized that a positive relationship exists between children's oral language proficiency and their written language performance. This study examined the following two aspects of the relationship between oral and written language: (a) Are specific linguistic components of language more closely related than others? (b) Do groups rated high, medium, or low on written language measures differ significantly in oral language proficiency? Measures of oral and written language were administered to 77 third-grade students. Results indicated that moderate relationships existed between grammatical aspects of oral and written language. Oral language proficiency was significantly different for groups rated high, medium, and low on the basis of written language performance.  相似文献   
984.
985.
986.
987.
This study aimed at investigating the relationship between intellectual, social, personal and personality variables of academically gifted secondary school students. A total of 297 tenth grade boys and girls were identified on the basis of three main criteria: 1. Academic achievement with special emphasis on Arabic language, science and math scores; 2. Behavioural traits; 3. General mental ability and general adjustment. Data related to socioeconomic status and personal characteristics were also collected. Results of the analysis of variance showed that there were significant differences between gifted and nongifted groups in general mental ability, achievement, general adjustment, behavioural traits, personal and social variables, in favour of the former.  相似文献   
988.
989.
The goal of this study was to examine the means used by textbook authors to introduce, define, and explain the mole concept in high school and introductory college chemistry textbooks. The analysis was framed by four questions:
  • 1 How is the mole defined?
  • 2 What concepts about the atom are introduced prior to the mole?
  • 3 Is Avogadro's constant presented as an experimentally determined value?
  • 4 What is the context for introducing the mole?
Twenty-nine high school and introductory college level chemistry texts were examined. After independent reading of appropriate sections of each text, discussion of differences, second or third readings of texts, and subsequent discussions, both authors reach 100% agreement concerning the results. Major conclusions were
  • 1 Two ways of defining the mole dominate the texts. One way defines the mole as Avogadro's number (6.02 × 1023) particles; the other method defines the mole in terms of carbon-12.
  • 2 All texts that present a definition in terms of C-12 introduce and define concepts about the atom prior to introducing the mole.
  • 3 Most texts at all levels point out that the value 6.02 × 1023 is an experimentally determined quantity.
  • 4 Nearly all texts discuss the mole in relation to die problem of finding a way to count particles that are too small to be directly weighed. Most texts also use a familiar counting unit, such as the dozen, to introduce the mole by analogy.
Four issues were discussed: (a) the defining attributes of the mole concept itself and the cognitive requirements for comprehending the two most frequently used definitions; (b) the connection between the definition of the mole presented in the text and the concepts about atoms that are introduced before the mole concept is developed; (c) the experimental nature of Avogadro's number; and (d) the context or setting for developing the mole concept.  相似文献   
990.
Cognitive theory suggests that a key to expert performance lies in the internal organization of the expert's knowledge. The authors contend that the type of technical illustration used during instruction influences knowledge organization and greatly impacts students' understanding of the content. This paper describes an experimental study that tested the impact of one type of conceptual illustration on students' understanding of the structure, function, and behavior of complex technical systems. The results show that supplementing traditional technical instruction with functional flow diagrams can improve overall system understanding. The functional flow diagrams were also found to be an effective instructional aid for enhancing students' conceptual understanding of the causal behavior of systems. In addition, the use of the functional flow diagram was found to significantly improve the subjects' ability to construct conceptual models that were similar to those of an expert. The implications of using conceptual diagrams for technical instruction are discussed and recommendations for future research in this area are provided.  相似文献   
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