Describes the use of the partial credit form of the Rasch model in the analysis and calibration of a set of writing tasks in which assessment scales and criteria were adapted to suit each task's specific demands. Potential applications of the partial credit model in language testing are discussed. (Author/CB)

Suggests that any model of washback must include insights from the theory of educational innovation to help explain why tests do not always have the desired or feared effect. Key concepts in educational innovation are reviewed, showing how these concepts are manifested in a case study in washback and outlining how they are being applied in recent…