ABSTRACT
This chapter focuses on the different types of language test scoring systems, with particular attention to scale design for performance-based tests in speaking and writing. It shows what scaling entails by introducing the advantages and disadvantages of rating scales, the types of rating scale used in assessment practice, and different approaches to scale development and validation. Alongside the presentation of the different types of scales, the chapter discusses different scale design methods and benchmarking, i.e., finding representative performances of each scalar level. Unlike the measurement-based approach that relies on intuitively derived, predetermined scale criteria and levels, a performance-based, data-driven approach is a bottom-up method. The chapter utilizes a hybrid approach to scale when developing a profile-based rating scale for English Placement Test, the English as a Second Language writing placement test at the University of Illinois at Urbana-Champaign. The scale descriptors need to be deconstructed to identify an array of relevant linguistic or extralinguistic features.
