Quality assurance in high schools through regression analysis

Watermeyer, John Westerton

Quality assurance in high schools through regression analysis

Master Thesis

1997

Publisher

University of Cape Town

Department

School of Education

Faculty

Faculty of Humanities

Abstract

School Effectiveness is a relatively new and poorly defined domain for which a structure is proposed, to facilitate future discussion. Three fields within School Effectiveness are identified, namely School Effectiveness Research (SER), School Improvement (SI) and Quality Assurance (QA). Three divisions are identified within each field on the basis of various criteria. SER has methodological generations, Sl is classified by decade, and three themes of QA are described, including performance indicators (Pis). A definition of effectiveness in terms of regression lines is described and the concept of added value or adjusted achievement developed. This study is concerned with the development of Pis for use within a single school to monitor and promote improvement. The context of the study (a model C senior high school in a predominantly white southern suburb of Cape Town) and the data collected is described before a review is made of some of the analyses which could be used to monitor effectiveness. A technique whereby pupil achievement is adjusted (for prior achievement and other background variables) and the residuals (or adjusted achievement) derived from the regressions investigated with one-way A NOVAs is described and tested using various models and subjects. With respect to groups, it is proposed that statistical significance of differences between mean residuals could be used as a PI. With respect to individual pupils, educators could set their own criterion for investigating cases where adjusted achievement is very large or very small. Statistical significance requires interpretation, however, and the role of professional judgement in modelling and monitoring adjusted achievement is discussed. The view that techniques such as regression analysis can only indicate when professional investigation and intervention might be necessary is stressed. It would seem unwise to rank teachers or subjects on the basis of adjusted achievement.