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Anne R. Fitzpatrick Valerie B. Link Wendy M. Yen George R. Burket Kyoko Ito Robert C. Sykes 《Journal of Educational Measurement》1996,33(3):291-314
In one study, parameters were estimated for constructed-response (CR) items in 8 tests from 4 operational testing programs using the l-parameter and 2- parameter partial credit (IPPC and 2PPC) models. Where multiple-choice (MC) items were present, these models were combined with the 1-parameter and 3-parameter logistic (IPL and 3PL) models, respectively. We found that item fit was better when the 2PPC model was used alone or with the 3PL model. Also, the slopes of the CR and MC items were found to differ substantially. In a second study, item parameter estimates produced using the IPL-IPPC and 3PL-2PPC model combinations were evaluated for fit to simulated data generated using true parameters known to fit one model combination or ttle other. The results suggested that the more flexible 3PL-2PPC model combination would produce better item fit than the IPL-1PPC combination. 相似文献
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Reading and Mathematics tests of multiple-choice items for grades Kindergarten through 9 were vertically scaled using the three-parameter logistic model and two different scaling procedures: concurrent and separate by grade groups. Item parameters were estimated using Markov chain Monte Carlo methodology while fixing the grade 4 population abilities to have a standard normal distribution. For the separate grade-groups scaling, grade groupings were linked using the Stocking and Lord test characteristic curve procedure. Abilities were estimated using the maximum-likelihood method. In either content area, scatterplots of item difficulty, discrimination, and ability estimates from the two methods showed consistently strong linear relationships. However, as grade deviated from the base grade of four, the best-fit linear line through the pairs of item discriminations started to rotate away from the identity line. This indicated the discrimination estimates from the separate grade-groups procedure for extreme grades to be, on average, higher than those from the concurrent analysis. The study also observed some systematic change in score variability across grades. In general, the two vertical scaling approaches yielded similar results at more grades in Reading than in Mathematics. 相似文献
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Complexation of π-conjugated ligands by metal or semimetal ions leads to the enhancement of the planarity and rigidity of π-conjugated systems. Boron, especially, has played a central role in the design of luminescent main-group complexes. However, these complexes still suffer the disadvantage of aggregation-caused quenching as well as typical organic fluorophores. It has recently been reported that some types of boron complexes exhibit the aggregation-induced emission (AIE) property. Moreover, AIE behavior from complexes and organometallic compounds composed of the other group 13 elements, such as aluminum and gallium, has emerged in this decade. These observations greatly encourage us to develop advanced functional materials based on the group 13 elements. Indeed, recent research has demonstrated that these classes of materials are potentially versatile scaffolds for constructing chromic luminophores, efficiently emissive π-conjugated polymers and so on. This review mainly describes AIE-active group 13 complexes with four-coordinate structures and their application as photo-functional materials. Proposed mechanisms of the origins of AIE behavior are briefly discussed. 相似文献
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Kyle R. Lynch Han C. G. Kemper Bruna Turi-Lynch Ricardo R. Agostinete Igor H. Ito Rafael Luiz-De-Marco 《Journal of sports sciences》2017,35(24):2421-2426
The objective of the present study was to investigate the effects of different sports on stress fractures among adolescents during a 9-month follow-up period. The sample was composed of 184 adolescents divided into three groups (impact sports [n = 102]; swimming [n = 35]; non-sports [n = 47]). The occurrence of stress fracture was reported by participants and coaches. As potential confounders we considered age, sex, resistance training, body composition variables and age at peak of height velocity. There were 13 adolescents who reported fractures during the 9-month period. Bone mineral density values were higher in adolescents engaged in impact sports (P-value = 0.002). Independently of confounders, the risk of stress fracture was lower in adolescents engaged in impact sports than in non-active adolescents (hazard ratio [HR] = 0.23 [95% confidence interval (CI) = 0.05 to 0.98]), while swimming practice was not associated to lower risk of fracture (HR = 0.49 [95% CI = 0.09 to 2.55]). In conclusion, the findings from this study indicate the importance of sports participation among adolescents in the reduction of stress fracture risk, especially with impact sports. More importantly, these results could be relevant for recognising adolescents in danger of not reaching their potential for peak bone mass and later an increased risk of fractures. 相似文献
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Ryo Ito Naoyuki Yamashita Eiko Suzuki Takaaki Matsumoto 《Journal of sports sciences》2015,33(9):892-898
Outdoor exercise often proceeds in rainy conditions. However, the cooling effects of rain on human physiological responses have not been systematically studied in hot conditions. The present study determined physiological and metabolic responses using a climatic chamber that can precisely simulate hot, rainy conditions. Eleven healthy men ran on a treadmill at an intensity of 70% VO2max for 30 min in the climatic chamber at an ambient temperature of 33°C in the presence (RAIN) or absence (CON) of 30 mm · h?1 of precipitation and a headwind equal to the running velocity of 3.15 ± 0.19 m · s?1. Oesophageal temperature, mean skin temperature, heart rate, rating of perceived exertion, blood parameters, volume of expired air and sweat loss were measured. Oesophageal and mean skin temperatures were significantly lower from 5 to 30 min, and heart rate was significantly lower from 20 to 30 min in RAIN than in CON (P < 0.05 for all). Plasma lactate and epinephrine concentrations (30 min) and sweat loss were significantly lower (P < 0.05) in RAIN compared with CON. Rain appears to influence physiological and metabolic responses to exercise in heat such that heat-induced strain might be reduced. 相似文献
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Banri Ito 《Research Policy》2007,36(8):1275-1287
The large expansion of MNC's overseas R&D is noteworthy. This paper investigates the factors affecting the expansion of support-oriented R&D and knowledge sourcing R&D by using qualitative data which indicate the modes of R&D conducted at a plant site and a laboratory. The empirical results suggest that (1) the export propensity of affiliate firms, relative abundance of human resources for R&D, and accumulated technological knowledge have a positive effect on both the modes of R&D at a plant site and a laboratory, and (2) the stronger enforcement of intellectual property positively affects the expansion of knowledge sourcing R&D. These results show that not only firm-specific but also country-specific factors positively affect the overseas expansion of R&D. 相似文献
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Student responses to a large number of constructed response items in three Math and three Reading tests were scored on two occasions using three ways of assigning raters: single reader scoring, a different reader for each response (item-specific), and three readers each scoring a rater item block (RIB) containing approximately one-third of a student's responses. Multiple group confirmatory factor analyses indicated that the three types of total scores were most frequently tau-equivalent. Factor models fitted on the item responses attributed differences in scores to correlated ratings incurred by the same reader scoring multiple responses. These halo effects contributed to significantly increased single reader mean total scores for three of the tests. The similarity of scores for item-specific and RIB scoring suggests that the effect of rater bias on an examinee's set of responses may be minimized with the use of multiple readers though fewer than the number of items. 相似文献
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John Schacter Jeff Shih Charles M. Allen Lina DeVaul Amy B. Adkins Taro Ito 《Early education and development》2016,27(1):74-88
Research Findings: Effective preschool mathematics instruction is especially important for low-income children. Previous research demonstrates that low-income children enter kindergarten behind their middle-income peers. They receive less mathematics support at home and from public preschools. The aim of this study was to test Math Shelf, a tablet intervention designed to improve at-risk preschoolers’ mathematics performance. A total of 100 children participated in a randomized controlled trial in a large urban Head Start center. Intervention students played Math Shelf on tablet computers for 6 weeks, whereas comparison students played the most downloaded and best reviewed preschool math apps on tablets for an equal amount of time. During game play, graduate student researchers supervised intervention and comparison students in separate rooms. Intervention and comparison groups did not differ on pretest assessments. Math Shelf students performed statistically significantly better (Cohen’s d = 0.57) than comparison students at posttest. Practice or Policy: Math Shelf results suggest that teachers can enhance low-income preschoolers’ mathematics knowledge in a relatively short amount of time by incorporating developmentally appropriate tablet interventions. 相似文献
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Masami Ito Ibrahim Elsheikh Godwin C. Chu Syed A. Rahim D. Lawrence Kincaid P. Gould 《Communication Booknotes Quarterly》2013,44(8):155-162
Masami Ito, et al. Broadcasting in Japan (London and Boston: Routledge & Kegan Paul, 1978—E4.95/$9.50, paper) Ibrahim Elsheikh Mass Media and Ideological Change in Egypt (1950-1973) (Amsterdam: University of Amsterdam, 1977—about $40.00, paper) Mass Media and Cultural Relationships by Anthony Piepe, Sunny Crouch and Miles Emerson (1978, 169 pp.—price not given) Trade Unionism in Television by Peter Seglow (1978, 287 pp.—price not given) Cuadernos de Comunicaci(5n (Communication Notes) (Comunicolgia Aplicada de Mexico, S.A. Comunal No. 7, Mexico 20, D.F.—about $55 per year/12 issues). Godwin C. Chu, Syed A. Rahim, and D. Lawrence Kincaid Institutional Exploration in Communication Technology (Honolulu: East West Communication Institute, East-West Center, 1978 —$3.00, paper) P. Gould and J. Johnson, An Experiment in the Classification of Television Programs, October 1978, $3.00, paper), and the paper written for laymen, #5 (P. Gould, How Should We Classify Television Programs? October 1978, $2.50, paper) Journalism Training: An Interim Report by Robert Amerson and John Herbst (30 pp. $1.75) An Analysis of Ten International Radio News Broadcasts in English to Africa by Douglas A. Boyd and Donald R. MacKay (16 pp., $1.25) A Look at the World's Radio News by Bert Cowlan and Lee M. Love (39 pp., $2.25) Education for Communication Development: The Global View by Robert Lindsay (27 pp., $1.75) A Brief Study on News Patterns in 16 Third World Countries by Edward T. Pinch (15 pp., $1.25) International Telecommunications and the Requirements of News Services by Ithiel de Sole Pool and Stephen Dizard (19 pp., $1.25) Foreign News in Nine Arab Countries by Gehan Rachty (21 pp., $1.25) International News Wires and Third World News in Asia by Wilbur Schramm, et al. (79 pp., $4.00) The Multinational News Pool by Roger Tatarian (19 pp., $1.25) International Conferences: Process and Effects by Rosemarie Rogers, et al. (March 1978, 53 pp., $3.00) Hemisphere Communications in Historical Perspective by James Nelson Goodsell (September 1978, 18 pp., $1.25) Kaarle Nordenstreng and Herbert I. Schiller, eds. National Sovereignty and International Communication (Norwood, N.J.: Ablex Publishing Corp., 1979—$21.50) Rosemary Righter's Whose News? Politics, the Press and the Third World (London: Andre Deutsch/New York: Times Books, 1978—$12.50) Frank Barton The Press of Africa: Persecution & Perseverance (New York: Holmes & Meier/Africana Publishing Co, 1979—$29.50) Godwin C. Chu, ed. Popular Media in China: Shaping New Cultural Patterns (Honolulu: University Press of Hawaii, 1978—$12.00) 相似文献