Predicting functional adequacy from complexity, accuracy, and fluency of second-language picture-prompted speaking

Abstract

Functional adequacy (FA) is a construct of task achievement in communicative settings and focuses on the extent to which task requirements are satisfied by effectively conveying intended messages. Recent studies in second-language speaking and writing have emphasized the importance of FA in addition to complexity, accuracy, and fluency (CAF); FA and CAF are combined into the acronym CAFFA. This study aims to investigate (a) the extent to which CAF measures can explain FA holistic ratings in oral picture narration among Japanese learners of English; (b) how these results are moderated by different picture tasks; and (c) the comparability of means, variances, and correlations of the same FA ratings and CAF measures across tasks. Results of multiple regression analyses indicate that only a speed fluency measure (syllables per minute) significantly predicts FA, while a substantial proportion of FA remains unexplained by CAF, highlighting the separate and related nature of the two constructs. Moreover, the prediction of FA by CAF is consistent across picture tasks, with means and variances of FA and CAF measures being generally comparable, and with correlations of the same measures across tasks not being consistently strong, except for syllables per minute. The paper discusses implications and offers suggestions for future research.