Coding mathematics items in the PISA assessment

Abstract

Coding of student responses is one of the most important, but also difficult processes of the PISA assessment. This chapter explains how this is done, without assuming any prior knowledge of PISA assessment. First the resources and procedures that are used in the course of the coding process are described: The coding guide and the general principles of coding. For better understanding, actual items are used to illustrate the multilayer structure of codes. There is an explanation of the elaborate preparations for the coding process, both within a participating country as well as globally, aimed at reaching a common understanding of codes within the international community of coders. After the long period of careful preparations the actual coding takes place. The actual coding process is explained by sharing the author’s experiences as a supervisor of coders during four consecutive PISA survey administrations. Examples illustrate the inevitable coding dilemmas, proving again and again that our students’ creativity exceeds the imagination of the most experienced coding guide authors. Examples also show how PISA can resolve such dilemmas in a systemic way.