ERIC Number: ED190608
Record Type: RIE
Publication Date: 1980-Mar
Reference Count: 0
Consideration for Sample Size in Reliability Studies for Mastery Tests. Publication Series in Mastery Testing.
Saunders, Joseph C.; Huynh, Huynh
In most reliability studies, the precision of a reliability estimate varies inversely with the number of examinees (sample size). Thus, to achieve a given level of accuracy, some minimum sample size is required. An approximation for this minimum size may be made if some reasonable assumptions regarding the mean and standard deviation of the test score distribution can be made. To facilitate the computations, tables are developed based on the Comprehensive Tests of Basic Skills. The tables may be used for tests ranging in length from 5 to 30 items, with percent cutoff scores of 60%, 70%, or 80%, and with examinee populations for which the test difficulty can be described as low, moderate, or high, and the test variability as low or moderate. The tables also reveal that for a given degree of accuracy, an estimate of kappa would require a considerably greater number of examinees than would an estimate of the raw agreement index. (Author)
Publication Type: Reports - Research; Speeches/Meeting Papers
Education Level: N/A
Sponsor: National Inst. of Education (DHEW), Washington, DC.
Authoring Institution: South Carolina Univ., Columbia. School of Education.
Identifiers: Comprehensive Tests of Basic Skills
Note: Paper presented at the Annual Meeting of the Eastern Educational Research Association (Norfolk, VA, March 5-9, 1980).