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71.
72.
Björn Öckert 《Economics of Education Review》2010,29(4):504-516
This paper exploits discontinuities and randomness in the college admissions in Sweden in 1982, to estimate the economic return to college in the 1990s. At the time, college admissions were highly selective and applicants were ranked with respect to their formal merits. Admissions were given to those ranked higher than some threshold value. At the margin, applicants were sometimes randomly assigned to college. Exploiting this Regression-Discontinuity design, individuals who were admitted in 1982 are estimated to have about 0.20 years longer college education in 1996. However, the earnings effects for applicants at the margin of admission are insignificant. Controlling for the college admission determinants, the OLS-estimates of the return to college is 1.4 percent in 1991–96. The IV-estimates are not significantly different from the OLS counterparts. 相似文献
73.
74.
The effects of query structures and query expansion (QE) on retrieval performance were tested with a best match retrieval system (InQuery1). Query structure means the use of operators to express the relations between search keys. Six different structures were tested, representing strong structures (e.g., queries with facets or concepts identified) and weak structures (no concepts identified, a query is a bag of search keys). QE was based on concepts, which were first selected from a searching thesaurus, and then expanded by semantic relationships given in the thesaurus. The expansion levels were (a) no expansion, (b) a synonym expansion, (c) a narrower concept expansion, (d) an associative concept expansion, and (e) a cumulative expansion of all other expansions. With weak structures and Boolean structured queries, QE was not very effective. The best performance was achieved with a combination of a facet structure, where search keys within a facet were treated as instances of one search key (the SYN operator), and the largest expansion. 相似文献
75.
In two experiments, saccharin (CS) and lithium chloride (US) were paired in a context consisting of specific visual, auditory, tactual, and olfactory cues. The saccharin aversion was then extinguished in a context free from conditioning-context cues. Later, saccharin preference tests were given in the presence and absence of these cues. The results indicated that the background cues of the conditioning trial controlled the amount of saccharin drunk on extinction trials, and, furthermore, that extinction of the taste aversion was context specific; i.e., groups given extinction trials in a different (from conditioning) context retained their saccharin aversion in the conditioning context only. The results indicate an important role played by the exteroceptive context in taste-aversion conditioning. 相似文献
76.
The purpose of the study was to examine whether students’ linguistic skills and task-avoidant behavior (i.e., the child-related factors) and the mean level of academic skills (reading comprehension and math) of classmates (i.e., the class-related factor) are associated with teacher judgments of children’s reading comprehension and math skills. The participants were third-grade Estonian-speaking students (n?=?656; age 9?11 years) and their classroom teachers (n?=?51). The results of the structural equation modeling path analyses indicated that teachers tend to judge students showing higher academic and linguistic skills and lower avoidance behavior as higher on the reading comprehension and math skills. In contrast, the classmates’ higher academic skill level was related to lower judgments of individual children’s reading comprehension and math skills by teachers. 相似文献
77.
78.
Mats Ekström Monika Djerf-Pierre Bengt Johansson Nicklas Håkansson 《Journalism Practice》2016,10(8):983-1004
News interviews are contexts in which political responsibilities are articulated and negotiated. Although the accountability interview is recognized as a commonsense practice in journalism, and the research on political interviews is substantial, it partly remains to explore how responsibilities are negotiated in different forms of questioning in journalism. This study investigates three generic forms of questioning: accountability questioning, the clarifying of promises, and the principal assessments. Key features of the different forms are specified. The empirical study investigates how the questionings are performed in news on industrial crises in Sweden, in the different political regimes in the 1970s and the 2000s. The data consist of 27 news interviews with the formally responsible Ministers. The method is based on Conversation Analysis and includes detailed analyses of questions and answers. The study shows (1) how the forms of questioning differ when it comes to the action agenda and in how responsibilities are invoked and negotiated; (2) how the questionings tend to reproduce particular expectations of Governmental interventions; (3) how increased assertiveness and adversarialness in interviewing coincide with reduced expectations of political responsibilities. 相似文献
79.
Filippo Abbondanza Philip S. Dale Carol A. Wang Marianna E. Hayiou-Thomas Umar Toseeb Tanner S. Koomar Karen G. Wigg Yu Feng Kaitlyn M. Price Elizabeth N. Kerr Sharon L. Guger Maureen W. Lovett Lisa J. Strug Elsje van Bergen Conor V. Dolan J. Bruce Tomblin Kristina Moll Gerd Schulte-Körne Nina Neuhoff Andreas Warnke Simon E. Fisher Cathy L. Barr Jacob J. Michaelson Dorret I. Boomsma Margaret J. Snowling Charles Hulme Andrew J. O. Whitehouse Craig E. Pennell Dianne F. Newbury John Stein Joel B. Talcott Dorothy V. M. Bishop Silvia Paracchini 《Child development》2023,94(4):970-984
Handedness has been studied for association with language-related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non-right-handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex-matched controls identified from 10 distinct cohorts (age range 6–19 years old; European ethnicity) using a priori set criteria. A meta-analysis (Ncases = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06–1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions. 相似文献
80.
This study examines the relationships between the environmental attitudes and environmental knowledge of schoolchildren within the framework of an environmental intervention. We employed questions from the 2-MEV model to monitor students’ environmental attitudes in terms of the model factors Preservation and Utilisation while concurrently monitoring three environmental knowledge dimensions (system, action-related and effectiveness knowledge) at three different test times during the course of a four-day field centre programme for fourth-graders (N = 133, Mage = 9.8 years). Probably due to measurement constraints (e.g. a ceiling effect, social desirability), we found no correlation between environmental knowledge and the attitude Preservation at all test times. The attitude Utilisation correlated negatively with all environmental knowledge dimensions, indicating that students who score higher on Utilisation are more likely, for example, to have and gain more system knowledge through programme participation than the other students or vice versa, as a causal relationship cannot be derived from our analyses: system knowledge may also influence Utilisation. In other words, children who refrain from (ab)using nature also seem to put more effort into improving their environmental knowledge and/or children who engage in learning about the environment will become less exploitative towards the environment. 相似文献