Using the Tolerance Principle to predict phonological change

Abstract

Language acquisition is a well-established avenue for language change (Labov, 2007). Given the theoretical importance of language acquisition to language change, it is all the more important to formulate clear theories of transmission-based change. In this paper, we provide a simulation method designed to test the plausibility of different possible transmission-based changes, using the Tolerance Principle (Yang, 2016) to determine precise points at which different possible changes may become plausible for children acquiring language. We apply this method to a case study of a complex change currently in progress: the allophonic restructuring of /æ/ in Philadelphia English. Using this model, we are able to evaluate several competing explanations of the ongoing change and determine that the allophonic restructuring of /æ/ in Philadelphia English is mostly likely the result of children acquiring language from mixed dialect input, consisting of approximately 40% input from speakers with a nasal /æ/ split. We show that applying our simulation to a phonological change allows us to make precise quantitative predications about the progress of this change. Moreover, it forces us to reassess intuitively plausible hypotheses about language change, such as grammatical simplification, in a quantitative and independently motivated framework of acquisition.

(æ)fter the storm: An Examination of the short-a system in Greater New Orleans

“…Despite the fact that many participants in this study featured a split or split-continuous short-a system, statistical analysis indicated that younger participants were more likely to feature nasal systems, confirming Labov's (2007) claim that a shift is in progress away from the split system toward adoption of a nasal system. This pattern mirrors such shifts taking place in NYC (Becker, 2010) and Philadelphia (Sneller, 2018) and follows broader trends throughout the US in terms of adoption of a nasal short-a system. Another significant predictor of short-a system type was extra-local orientation, with speakers featuring a higher extra-local orientation score (those most oriented away from Chalmette) more likely to feature the transitional nasal-continuous system.…”

“…This brings up the question of awareness. In Philadelphia, Sneller (2018) used a matched guise test to demonstrate that split versus nasal systems in the city are above the level of conscious awareness and carry social meaning. This contrasts with Eckert and Labov's (2017) suggestion that the abstract phonological organization of one's sound system—mergers, splits, and chain shifts—are not as readily available for the development of indexical social meaning as phonetic gestures are, due to the referential weight that a phonological system carries, and the frequent lack of awareness linked to such complex sound relationships.…”

“…The nasal system is also more common in the US on the whole, thus allowing speakers exposure to it on television and social media and also likely during their displacement following Hurricane Katrina. In other shifting communities, migrating populations to the region in question have been cited as the source of the nasal system (see Sneller [2018] on Philadelphia). As mentioned, there is evidence that the nasal system had arrived in New Orleans before the storm, pointing to its potential appearance via migrant populations pre-Katrina, rather than it being a result of contact due to post-Katrina displacement.…”

“…Split systems have been argued to be present currently and/or historically in a number of locales, including Cincinnati, Ohio (Boberg & Strassel, 2000), New Orleans (Labov, 2007), the Hudson River Valley (Dinkin, 2009), Columbus, Ohio (Durian, 2012), and parts of New England (Johnson & Durian, 2016), though they are most characteristic of the Mid-Atlantic region of the US, in particular the areas surrounding New York City (Becker, 2010; Labov, 2006[1966]), and Philadelphia (Labov, 1989; Sneller, 2018), and to some extent the regions in between (Ash, 2002). Labov (2007) has argued that the presence of split short-a systems outside of the mid-Atlantic represents a case of diffusion on the basis of the system's simplification in these regions.…”

Drift as a driver of language change: An artificial language experiment

“…Here, we report on the first artificial-language experiment quantifying both drift and selection during language acquisition in an effort to understand how word frequency is related to rates of replacement and regularisation. Language acquisition is widely thought to be the most important stage for language change [13,14,15,16,17]. Language-learning experiments using artificial languages have already revealed several factors-including learning, age, memory, and multigenerational transmission-that up-and down-regulate regularisation during language acquisition [18,19,20,21,17,22,23].…”