A phonotactic grammar assigns a well-formedness score to all possible surface forms. This paper considers whether phonotactic grammars should be probabilistic, and gives several arguments that they need to be. Hayes & Wilson (2008) demonstrate the promise of a maximum entropy Harmonic Grammar as a probabilistic phonotactic grammar. This paper points out a theoretical issue with maxent phonotactic grammars: they are not guaranteed to assign a well-defined probability distribution, because sequences that contain arbitrary repetitions of unmarked sequences may be underpenalised. The paper motivates a solution to this issue: include a *Struct constraint. A mathematical proof of necessary and sufficient conditions to avoid the underpenalisation problem are given in online supplementary materials.

Listeners often perceive illusory vowels when presented with consonant sequences that violate phonotactic constraints in their language. Previous research suggests that the phenomenon motivates speech-perception models that incorporate surface phonotactic information and the acoustics of the speech tokens. In this article, inspired by Bayesian models of speech perception, we claim that the listener attempts to identify target phonemic representations during perception. This predicts that the phenomenon of perceptual illusions will be modulated not only by surface phonotactics and the acoustics of the speech tokens, but also by the phonological alternations of a language. We present the results of three experiments (an AX task, an ABX task and an identification task) with native Korean listeners, and native English listeners as a control group, showing that Korean listeners perceive different sets of illusory vowels in different phonological contexts, in accordance with the phonological processes of vowel deletion and palatalisation in the language.

This paper explores the variable application of n-insertion in Korean. Several tendencies emerge from the distribution of n-insertion in existing Korean words, using data drawn from a dictionary and from surveys and experimental studies. Most, but not all, of these tendencies are mirrored in the results of experiments involving novel words, suggesting that Korean speakers are aware of the differential influence of certain phonological factors on the probability of the application of n-insertion. The observed patterns of variation are analysed within the framework of a probabilistic version of Optimality Theory. In addition, the paper shows that the main aspects of n-insertion are motivated by the requirement of perceptually minimal modification, employing an analysis based on Steriade's P-map theory. The observed data vs. learning mismatch is also attributed to the lack of a perceptual basis for the tendency in question.

This article presents a novel OT analysis of ternary rhythm, using the restrictive format of McCarthy (2003)'s categorical alignment constraints, which we will refer to as ‘non-intervention constraints’, using the terminology of Ellison (1994), and argues for the rehabilitation of internally layered feet in metrical representations (i.e. feet with one layer of recursion). By means of a computer-generated factorial typology, we demonstrate that the constraint set proposed here generates the full typology of binary and ternary rhythm. The resulting typology suggests that there is no absolute boundary between binary and ternary systems; rather, a continuum emerges, such that binary and ternary feet may coexist in rhythmic stress systems.

This paper presents an overview of the Parallel Encoding and Target Approximation (PENTA) model of speech prosody, in response to an extensive critique by Arvaniti & Ladd (2009). PENTA is a framework for conceptually and computationally linking communicative meanings to fine-grained prosodic details, based on an articulatory-functional view of speech. Target Approximation simulates the articulatory realisation of underlying pitch targets – the prosodic primitives in the framework. Parallel Encoding provides an operational scheme that enables simultaneous encoding of multiple communicative functions. We also outline how PENTA can be computationally tested with a set of software tools. With the help of one of the tools, we offer a PENTA-based hypothetical account of the Greek intonational patterns reported by Arvaniti & Ladd, showing how it is possible to predict the prosodic shapes of an utterance based on the lexical and postlexical meanings it conveys.

We are naturally pleased that Xu et al. (2015) have taken the trouble to address our critique of the PENTA model, and it is useful to have a concise restatement of PENTA's aims and assumptions. However, we believe that their reply does not address the key point of our earlier paper (Arvaniti & Ladd 2009), which was that syllable-by-syllable specification of F0 does not makes theoretical sense in a language where F0 functions at the phrase or utterance level, and does not permit adequate quantitative modelling of complex intonation contours in short utterances.