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991.
Alain Desrosières 《Minerva》2009,47(3):307-322
Are the categories used to study the social world and acting on it “real” or “conventional”? An empirical answer to that question is given by an analysis of the debates about the “quality” of statistics produced by the European National Institues of statistics in the 1990s. Six criteria of quality were then specified: relevance, accuracy, timeliness, accessibility, comparability and coherence. How do statisticians and users of statistics deal with the tension produced by their objects being both “real” (they exist before their measurement) and “conventionally constructed” (they are in a way, created by these conventions)? In particular, the technical and sociological distinction between the criteria of relevance and accuracy implies a realistic interpretation, desired by users, but that is nonetheless problematic. 相似文献
992.
A. A. Akhrem V. Z. Rakhmankulov K. V. Yuzhanin 《Scientific and Technical Information Processing》2017,44(6):406-411
In this paper, decomposition methods for multidimensional data hypercubes of OLAP systems are investigated. Criteria for reducing the computational complexity of the decomposition methods are presented and comparisons are made with the traditional solutions of multidimensional data analysis problems. Examples illustrating the application of these criteria to investigating the dynamics of computational complexity changes for specific types of reduction problems are considered. 相似文献
993.
994.
求解有约束最优化问题的不连续罚函数积分总极值法 总被引:1,自引:0,他引:1
1IntroductionLetXbe a topological space ,Sa nonempty subsetofXandf:X→Ra real-valued function.Consider thefollowing constrained opti mization problem:c*=infx∈Sf(x) , (1)and the set of global mini mizers :H*={x∈S|f(x) =c*} (2)under the assumptions (see Refs .[1] and [2]) :(A) :fis lower semi-continuous ,Sis closed andthere is a real numberbsuch that the setHb={x∈S|f(x)≤b} is a nonempty compact set ;(R) :fis upper robust onS,i.e.,{x∈S|f(x) 相似文献
995.
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
996.
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
997.
Mehmet Demir 《Educational technology research and development : ETR & D》2018,66(6):1457-1477
This study investigates the development of an instrument to explore the views of student teachers in Turkey towards using Facebook as a tool for teaching and learning. A five-point Likert-type scale was developed for a sample of 687 student teachers from various fields in Adiyaman, Mustafa Kemal, and Inonu Universities. The sample included 445 participants in the first application and 242 participants in the second. A literature review, students’ comments, and relevant Facebook research results were considered in order to establish the items for the scale. A comparative analysis of previous studies and instruments yielded an original 33-item pool, and experts’ judgments were consulted to confirm the content validity of the scale. Exploratory and confirmatory factor analyses were conducted to determine the factor structure of the scale, revealing 17 items that could be grouped under three general factors. A Cronbach’s coefficient (α) was employed to determine the internal consistency coefficients for the whole scale and its subscales. Results indicate that this learning scale (FLTS) is a valid and reliable instrument to investigate the use of Facebook as a learning tool. 相似文献
998.
S. N. Maitra 《Resonance》2012,17(4):378-386
In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing
with them, or invite responses, or both. “Classroom” is equally a forum for raising broader issues and sharing personal experiences
and viewpoints on matters related to teaching and learning science. 相似文献
999.
Kwok K. Ho 《科学教学研究杂志》1982,19(9):761-767
This study investigated the relationship between physics achievement and language of instruction in a situation where instruction was in the second language of both students and teachers. One hundred and seventy-six grade ten physics students (first language was Chinese) were selected from four classes of two secondary schools in Hong Kong. For three months (with four lessons per week), two classes of students learned the content material (light and sound) in Chinese and two classes learned the material in English. Group differences were controlled by using individual aptitude scores as covariates in the analysis. There were no differences in achievement, students' motivation, and effort spent in physics in that controlled teaching period. This was probably because the Anglo-Chinese group was sufficiently proficient in English so they did not encounter additional difficulty in learning physics when compared with the Chinese group. 相似文献
1000.
Leslie G. Adebonojo 《College & Undergraduate Libraries》2013,20(4):398-412
Reference librarians at East Tennessee State University's Sherrod Library identified LibGuides as an efficient way to introduce undergraduate students, particularly those in their first two years of college, to the university library. Selecting pertinent library resources based on a course syllabus and creating a LibGuide for the course provides the students with a limited number of relevant materials. Librarians and professors view the use of subject guides attached to a course management system site as an effective educational solution. Librarians facing exponentially expanding resources and first-year students who are used to turning to Google for all their information needs can utilize LibGuides to guide students toward more relevant library resources. 相似文献