The Method of Reducing the Variance of Person-by-task on Math Performance Assessment—Using Generalizability Theory

• Main Authors: Yi-Yu Chen, 陳怡玉
• Other Authors: Hue-Ying Tzou
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/83242439931570141297

碩士 === 國立臺南大學 === 測驗統計研究所 === 93 === The purpose of this study was to investigate the impact of task stratification and the scaffolding by using graphic organizers on person-by-task variances, generalizability coefficients, and indices of dependability. The subjects came from two classes of 4th grade. One was the researcher，s class and the other class had a teacher with the same teaching experience as the researcher. Two variables were manipulated in this study, task stratification and using the graphic organizer as the scaffolding. A completely crossed design and tasks nested within stratifications design were compared to examine the effects of task stratification. The researcher class accepted the instruction with graphic organizer as the scaffolding. The other class had the general instruction following the teaching guide. During the experiment, two classes received identical math class periods and homework. After the experiment, two classes were given the same math performance assessment. The variances of person-by-task in two classes were compared to examine the effect of scaffolding. The main results were as follows: 1.The task stratification couldn，t reduce p×t variance well, because the stratification variable was inappropriate. 2.The scaffolding by using graphic organizers could reduce p×t variance. 3. The method of using graphic organizer as the scaffolding performed better than the method of task stratification. 4.Considering the effect of task stratification, a single stratified assessment, which used the p×T×R design, had the largest generalizability coefficient. However, the stratified design p×（T：S）×R which generalizability coefficient was lower than the un-stratified design. 5.The method of scaffolding by using graphic organizers could raise the generalizability coefficient of math performance assessment.