NAP-Science Literacy 2018 Technical Report

This report describes the technical aspects of the NAP–SL 2018 sample assessment and summarises the main activities involved in the data collection, the data collection instruments and the analysis and reporting of the data and should be read in conjunction with the 2018 NAP–SL Public Report, which focuses on results and key findings (ACARA, 2019). Chapter 2 summarises the development of the assessment framework and describes the process of item development and construction of the instruments. Chapter 3 reviews the sample design and describes the sampling process. It also describes 12 2018 NAP–SL Technical Report OFFICIAL the weighting procedures that were implemented to derive population estimates and the calculation of participation rates. Chapter 4 summarises the field administration of the assessment. Chapter 5 deals with management procedures, including quality control and the cleaning and coding of the data. Chapter 6 describes the scaling model and procedures, item calibration, the creation of plausible values and the standardisation of student scores. It discusses the procedures used for vertical (Year 6 to Year 10) and horizontal (2018 to 2015, 2012, 2009 and 2006) equating and the procedures for estimating equating errors. Chapter 7 outlines the achievement levels and the procedures undertaken to determine the new proficient standard for Year 10 students. Chapter 8 discusses the reporting of student results, including the procedures used to estimate sampling and measurement variance