Testing claims of a usage-based phonology with Liverpool English t-to-r

The variable phenomenon in which /t/ can be realized as a tap or rhotic approximant in varieties of Northern British English (commonly referred to as t-to-r, Wells 1982: 370) has received some attention in English linguistics as debates have appeared over how best to model its phonology (e.g. Carr 1991; Docherty et al. 1997; Broadbent 2008). The occurrence of t-to-r seems to be constrained by the preceding and following phonological environment in a largely systematic way and so it is often accounted for within a rule-based model of grammar. Problematically, however, the rule does not apply blindly across the board to all words which fit the specified phonological pattern. Instead, t-to-r shows evidence of being lexically restricted, and this fact has recently encouraged a usage-based interpretation. Until now, there has been relatively little attempt to test the usage-based thesis directly with fully quantified data gleaned from naturally occurring conversation. This article investigates the extent to which certain usage-based predictions can account for variation attested in t-to-r in Liverpool English. Using oral history interviews with Liverpool English speakers born in the early 1900s, we examine the usage-based predictions first proposed by Broadbent (2008) that t-to-r is more likely in (a) high-frequency words and (b) high-frequency phrases. There is some support for the importance of lexical frequency as a motivating factor in the use of t-to-r, but our data do not fully support either of these claims wholesale. We suggest that t-to-r is not constrained simply by word frequency or phrase frequency alone, but by a combination of both. Finally, we explore the possibility of employing notions from Cognitive Grammar such as schema strength (e.g. Taylor 2002; Bybee 1995: 430) in our interpretation of these data