Publications

Abstract : Various learning disabilities affect spelling and handwriting abilities of children. An understanding of these disabilitiesis facilitated by developing a formal model of the cognitive processes involved in spelling. One such model is the dual-route model which was originally proposed for reading but can also be applied to spelling by evaluating the cognitive steps in a different order. The model is language-dependent. To develop a spelling model for Malayalam-English bilingual learners in Kerala, South India, we conducted a spelling study with 208 second grade students from seven schools. We then fitted a Bayesian dual-route modelto the data using an expectation-maximization (EM) algorithm. The model used 4 hidden variables to represent the stages in the cognitive process and 13 observed variables to represent the various types of spelling errors. The performance of the model was evaluated using cross-validation, and it was found that the dual-route model outperforms single-route models.