{"title":"Evaluating Random and Systematic Error in Student Growth Percentiles","authors":"C. Wells, S. Sireci","doi":"10.1080/08957347.2020.1789139","DOIUrl":null,"url":null,"abstract":"ABSTRACT Student growth percentiles (SGPs) are currently used by several states and school districts to provide information about individual students as well as to evaluate teachers, schools, and school districts. For SGPs to be defensible for these purposes, they should be reliable. In this study, we examine the amount of systematic and random error in SGPs by simulating test scores for four grades and estimating SGPs using one, two, or three conditioning years. The results indicated that, although the amount of systematic error was small to moderate, the amount of random error was substantial, regardless of the number of conditioning years. For example, the standard error of the SGP estimates associated with an SGP value of 56 was 22.2 resulting in a 68% confidence interval that would range from 33.8 to 78.2 when using three conditioning years. The results are consistent with previous research and suggest SGP estimates are too imprecise to be reported for the purpose of understanding students’ progress over time.","PeriodicalId":51609,"journal":{"name":"Applied Measurement in Education","volume":"33 1","pages":"349 - 361"},"PeriodicalIF":1.1000,"publicationDate":"2020-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957347.2020.1789139","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Measurement in Education","FirstCategoryId":"95","ListUrlMain":"https://doi.org/10.1080/08957347.2020.1789139","RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"EDUCATION & EDUCATIONAL RESEARCH","Score":null,"Total":0}
引用次数: 2
Abstract
ABSTRACT Student growth percentiles (SGPs) are currently used by several states and school districts to provide information about individual students as well as to evaluate teachers, schools, and school districts. For SGPs to be defensible for these purposes, they should be reliable. In this study, we examine the amount of systematic and random error in SGPs by simulating test scores for four grades and estimating SGPs using one, two, or three conditioning years. The results indicated that, although the amount of systematic error was small to moderate, the amount of random error was substantial, regardless of the number of conditioning years. For example, the standard error of the SGP estimates associated with an SGP value of 56 was 22.2 resulting in a 68% confidence interval that would range from 33.8 to 78.2 when using three conditioning years. The results are consistent with previous research and suggest SGP estimates are too imprecise to be reported for the purpose of understanding students’ progress over time.
期刊介绍:
Because interaction between the domains of research and application is critical to the evaluation and improvement of new educational measurement practices, Applied Measurement in Education" prime objective is to improve communication between academicians and practitioners. To help bridge the gap between theory and practice, articles in this journal describe original research studies, innovative strategies for solving educational measurement problems, and integrative reviews of current approaches to contemporary measurement issues. Peer Review Policy: All review papers in this journal have undergone editorial screening and peer review.