The Tool for Automatic Analysis of Decoding Ambiguity (TAADA)

Abstract This study documents and assesses the Tool for Automatic Analysis of Decoding Ambiguity (TAADA). TAADA calculates measures related to decoding, including metrics for grapheme and phoneme counts, neighborhood effects, rhymes, and conditional probabilities for sound–spelling relationships. These measures are assessed in two reading studies. The first study examined links between decoding variables and judgments of reading ease in a corpus of ~5000 reading excerpts, finding that variables related to word frequency, phonographic neighbors for words, word syllable length, and the reverse prior probability for consonants explained 34% of the variance in the reading scores. The second examined links between decoding variables and student reading miscues, finding that word frequency, phoneme counts, rhyme counts, and probability counts explained 3% of students’ reading miscues.