Predicting L2 achievement: Results from a test battery measuring language aptitude, general learning ability, and affective factors

This chapter addresses the following questions: How, and how accurately, can the children’s performance on a L2 English proficiency test administered around age 12 (T3) be predicted on the basis of test and questionnaire data that were collected one-and-a-half years earlier (T1)? The analyses suggest that a fairly simple equation can predict the score at T3 on new data with an average error of 1.8 points on a 20-point scale. This equation contains seven input variables available at T1. This accuracy corresponds to a R2 of 0.58. The seven input variables comprise questionnaire-based affective variables, as well as aptitude measures and German (the pupils’ school language) reading test data. Most of the heavy lifting, however, is donebyanEnglishproficiencytestadministeredatT1,whichbyitselfcanpredict new T3 data with an average error of 2.0 points (R2 = 0.41).