Modeling Perceived Similarity: The Influence of Phonetics, Phonology and Frequency on the Perception of French Vowels Abstract This paper examines the role of and interaction among a variety of factors known to influence perceived similarity, by examining vowel confusions in European French. It is shown that although acoustic similarity plays the greatest role in predicting perceived similarity, the phonological factors of degree of complementary distribution and functional load are also significant, with more predictably distributed sounds and sounds with lower functional loads being perceived as more similar. Frequency of occurrence seems to be relevant only for predicting asymmetrical confusions, i.e., cases where one sound (the less frequent) is mistaken for another (the more frequent) more than vice versa. The relevant factors are shown to be most usefully measured with direct reference to the lexicon, suggesting models of phonology in which phonological generalizations emerge indirectly via abstractions over word-forms, rather than directly from the phonetics. 1. Introduction Several factors are known to influence the perceived similarity of speech sounds. Most evident are the acoustic/auditory properties of the sounds in question, foundational to any model of perceptual similarity. Additionally, there is evidence, suggestive in some cases, that other less obvious factors relating to a language’s phonological system and patterns of usage also play a role. With respect to the influence of phonological systems on speech perception, evidence comes from a variety of sources. These include studies of first and second language acquisition showing that one’s perceptual system is shaped by native language experience (e.g. Best et al. 1988; Kuhl et al. 1992; Polka & Werker 1994). Further, the phonological status of a pair of sounds as contrastive or allophonic also plays a role: contrastive pairs of sounds are generally perceived to be less similar and less confusable than allophonic pairs of sounds (e.g., Jaeger 1980; Ohala 1982; Dupoux, Pallier, Sebastian & Mehler, 1997; Whalen, Best & Irwin 1997; Huang 2001; Hume & Johnson 2003; Kazanina, Phillips & Idsardi 2006; Boomershine, Hall, Hume, & Kathleen Currie Hall (University of British Columbia) & Elizabeth Hume (University of Canterbury) 22 August 2015. submitted.