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21.
The State of the Art in Text Filtering   总被引:1,自引:0,他引:1  
This paper develops a conceptual framework for text filtering practice and research, and reviews present practice in the field. Text filtering is an information seeking process in which documents are selected from a dynamic text stream to satisfy a relatively stable and specific information need. A model of the information seeking process is introduced and specialized to define text filtering. The historical development of text filtering is then reviewed and case studies of recent work are used to highlight important design characteristics of modern text filtering systems. User modeling techniques drawn from information retrieval, recommender systems, machine learning and other fields are described. The paper concludes with observations on the present state of the art and implications for future research on text filtering. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
22.
Reviews the book, Human cognitive abilities: A survey of factor-analytic studies by J. B. Carroll (see record 1993-97611-000). Carroll divides his book into three parts. The first is a historical and conceptual review of psychometric theory. Carroll begins by clearly defining and differentiating key concepts such as ability, aptitude, achievement, latent trait, and intervening variable, although recognizing that in practice it is often difficult to make absolute distinctions. The second part, and the bulk of the book, is a detailed analysis and synthesis of a myriad of findings in the area of cognitive abilities. In the third part of his book, Carroll summarizes his undertaking and addresses traditional concerns and controversies. He compares and contrasts his model of cognitive abilities with that of others. Although Carroll's book does not and indeed cannot resolve the issues and controversies concerning the nature of human cognitive abilities, it does represent a notable contribution to our ongoing endeavours. It undoubtedly is a book that anyone interested in cognitive abilities would wish to explore because of its encyclopedic, in-depth coverage of the topic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
24.
Reports 2 cued recall experiments in which younger and older Ss studied target words varying in number of preexperimental associates. In Exp 1, targets were studied in either the absence or presence of meaning-related context cues, with recall always prompted by the cues. In the absence of context, words with smaller sets of associates were easier to recall than those with larger sets, but this effect was reduced for older Ss. The presence of a study context cue facilitated recall and eliminated the effect of associative set size for both ages. In Exp 2, targets were studied and tested in the presence of unrelated words. In this situation, words with smaller sets of associates were less likely to be recalled than words with larger sets; again the effect was reduced for older Ss. The results are interpreted as an age decrement in processing implicitly activated information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
A meta-analysis that combined 33 correlations from 17 studies found a corrected average correlation of .330 between absence and turnover. The type of absence measure did not moderate the covariation between absence and turnover, but industry type and study duration did act as moderators. The results are discussed in the context of the "withdrawal" approach to understanding employee behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
26.
This article describes the development and validation of scales to measure clients' outcome optimism, perceived progress, and self-agency related to change in problems presented in therapy. In Study 1, initial confirmatory and subsequent exploratory factor analyses (N?=?257) identified effort and persistence as an additional unique factor and guided selection of items to measure the 4 constructs. In Study 2, confirmatory factor analysis of the revised scales with a new sample (N?=?93) confirmed the measurement model. Results of convergent and discriminant validity analyses generally were in the predicted directions. The Perceived Progress scale demonstrated criterion validity with changes in dyadic adjustment and family functioning. The Outcome Optimism and Self-Agency scales showed variability in their relationship to the Perceived Progress scale over the first 3 sessions of therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
Ben M. Benjamin  Emily C. Douglas 《Fuel》1986,65(12):1735-1739
The object of this paper is to demonstrate the usefulness of the transalkylation reaction for determining chemical structural features of products derived from coal. For example, the method is applied to derivatized coals, coals modified by thermolysis, and materials physically or chemically separated from coals. Data are presented for the pyridine soluble and insoluble parts of two coals, an O-methylated coal, a Birch reduced coal, a solvent refined coal, and a coke. Similarities and differences in chemical make-up of these materials are discussed.  相似文献   
28.
Findings of 7 studies suggested that decisions about the sex of a face and the emotional expressions of anger or happiness are not independent: Participants were faster and more accurate at detecting angry expressions on male faces and at detecting happy expressions on female faces. These findings were robust across different stimulus sets and judgment tasks and indicated bottom-up perceptual processes rather than just top-down conceptually driven ones. Results from additional studies in which neutrally expressive faces were used suggested that the connections between masculine features and angry expressions and between feminine features and happy expressions might be a property of the sexual dimorphism of the face itself and not merely a result of gender stereotypes biasing the perception. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
29.
In four experiments we evaluated aspects of the hypothesis that word-fragment completion depends on the results of lexical but not semantic search. Experiment 1 showed that the number of meaningful associates linked to a studied word does not affect its recovery when the test cue consists of letters and spaces for missing letters. Experiments 2 and 3 showed retroactive interference effects in fragment completion when words in a second list were lexically related to words in a first list but not when the words in the second list were meaningfully related. Experiment 4 indicated that for studied words, instructions to search at the word level facilitated completion performance and that instructions to generate letters to fill missing spaces had no effect. Other findings indicate that completion was affected by the number of words lexically related to the fragment and by the number of letters missing from the fragment. In general, experimental manipulations that focused on lexical characteristics were effective, and those that focused on semantic characteristics were ineffective. The findings support the conclusion that word fragments engender a lexical search process that does not depend on retrieving encoded meaning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
30.
Studied the relation between life stress and immune parameters for 33 30–70 yr old female rheumatoid arthritis (RA) patients interviewed during 3 routine monthly clinic checkups. Life stress from major and minor events, coping efficacy, and self-reported psychological distress were assessed, and immunofluorescence of T-cells and B-cells was performed on the blood drawn during each visit. Small stressful events were positively related to the proportion of circulating B-cells, psychological distress was inversely related to proportion of circulating T-cells, and major life events were associated with lower T-helper/T-suppressor cell ratios. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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