Dr Sacha Beniamine

Abstract Autonomous morphology, such as inflection class systems and paradigmatic distribution patterns, is widespread and diachronically resilient in natural language. Why this should be so has remained unclear given that autonomous morphology imposes learning costs, offers no clear benefit relative to its absence and could easily be removed by the analogical forces which are constantly reshaping it. Here we propose an explanation for the resilience of autonomous morphology, in terms of a diachronic dynamic of attraction and repulsion between morphomic categories, which emerges spontaneously from a simple paradigm cell filling process. Employing computational evolutionary models, our key innovation is to bring to light the role of ‘dissociative evidence’, i.e., evidence for inflectional distinctiveness which a rational reasoner will have access to during analogical inference. Dissociative evidence creates a repulsion dynamic which prevents morphomic classes from collapsing together entirely, i.e., undergoing complete levelling. As we probe alternative models, we reveal the limits of conditional entropy as a measure for predictability in systems that are undergoing change. Finally, we demonstrate that autonomous morphology, far from being ‘unnatural’, is rather the natural (emergent) consequence of a natural (rational) process of inference applied to inflectional systems.

Eesthetic is a collection of Estonian verbal and nominal paradigms, in phonemic and orthographic notation. They are suited for both computational and manual analysis. The dataset conforms to the Paralex standard

This paper contributes to addressing the Paradigm Cell Filling Problem (PCFP) in inflectional paradigms, as defined by Ackerman et al. (2009). We define a method for extending the use of conditional entropy to address the PCFP to prediction based on multiple paradigm cells. We apply this method to French and European Portugese and show that, on average, knowledge of multiple paradigm cells is dramatically more predictive than knowledge of a single cell. Moreover, this new entropy measure proves useful in studying principal parts systems, which correspond to sets of predictors yielding a null entropy. Using a graded measure allows us to highlight the relevance of non-categorical or "good enough" principal parts systems.

Linguists seek insight from all human languages, however accessing information from most of the full store of extant global linguistic descriptions is not easy. One of the most common kinds of information that linguists have documented is vernacular sentences, as recorded in descriptive grammars. Typically these sentences are formatted as interlinear glossed text (IGT). Most descriptive grammars, however, exist only as hardcopy or scanned pdf documents. Consequently, parsing IGTs in scanned grammars is a priority, in order to significantly increase the volume of documented linguistic information that is readily accessible. Here we demonstrate fundamental viability for a technology that can assist in making a large number of linguistic data sources machine readable: the automated identification and parsing of interlinear glossed text from scanned page images. For example, we attain high median precision and recall (>0.95) in the identification of example sentences in IGT format. Our results will be of interest to those who are keen to see more of the existing documentation of human language, especially for less-resourced and endangered languages, become more readily accessible.

We introduce the Romance Verbal Inflection Dataset 2.0, a multilingual lexicon of Romance inflection covering 74 varieties. The lexicon provides verbal paradigm forms in broad IPA phonemic notation. Both lexemes and paradigm cells are organized to reflect cognacy. Such multi-lingual inflected lexicons annotated for two dimensions of cognacy are necessary to study the evolution of inflectional paradigms, and test linguistic hypotheses systematically. However, these resources seldom exist, and when they do, they are not usually encoded in computationally usable ways. The Oxford Online Database of Romance Verb Morphology provides this kind of information, however, it is not maintained anymore and is only available as a web service without interfaces for machine-readability. We collect its data and clean and correct it for consistency using both heuristics and expert annotator judgements. Most resources used to study language evolution computationally rely strictly on multilingual contemporary information, and lack information about prior stages of the languages. To provide such information, we augmented the database with Latin paradigms from the LatInFlexi lexicon. Finally, to make it widely avalable, the resource is released under a GPLv3 license in CLDF format.

Recent literature has highlighted the extent to which inflectional paradigms are organised into systems of implications allowing speakers to make full use of the inflection system on the basis of exposure to only a few forms of each word. The present paper contributes to this line of research by investigating in detail the implicative structure of European Portuguese verbal paradigms. After outlining the computational methods we use to that effect, we deploy these methods on a lexicon of about 5000 verbs, and show how the morphological and phonological properties of European Portuguese verbs lead to the observed patterns of predictability.

Stem allomorphy plays a central role in the recent history of morphology, in no small part thanks to a research program initiated by Aronoff (1994). Yet, there is no agreed upon way of deciding whether some bit of form should be considered a proper part of a stem allomorph or an independent exponent. We explore the possibility of just doing away with the notion of stem allomorphy in inflection. We use computational methods to identify within each word a sequence of strings that do not take part in any alternation within that word’s paradigm. We then discuss the relationship of such sequences to the classical notion of a stem, and argue that discontinuous stems are both conceptually and empirically more satisfactory.

This paper discusses the nature of inflection classes (ICs) and provides a fully im-plemented methodology to conduct typological investigations into their structure.ICs (conjugations or declensions) are sets of lexemes which inflect similarly. Theyare often described as partitioning the set of lexemes, but similarities across classeslead some authors to favor hierarchical descriptions. While some formalisms allowfor multiple inheritance, where one class takes after two or more others, it is usuallytaken as an exceptional situation.I submit that the structure of ICs is a typological property of inflectional systems.As a result, ICs are best modelled as semi-lattices, which by design capture non-canonical phenomena. I show how these monotonous multiple inheritance hierar-chies can be inferred automatically from raw paradigms using alternation patternsand formal concept analysis. Using quantitative measures of canonicity, I comparesix inflectional systems and show that multiple inheritance is in fact pervasiveacross inflectional systems.

This is a collection of European Portuguese verbal paradigms, in phonemic notation. They are suited for both computational and manual analysis.

Most models of inflectional morphology rely at their core on the identification of recurrent and diverging material across inflected forms. Across theoretical frameworks, this can be expressed in terms of morpheme segmentation, rules, processes, patterns or analogies. Finding these recurrences in large structured lexicons is an important step in empirical computational morphology, where analyses are induced bottom-up from inflected forms. This can be done by aligning all the forms in each paradigm, a task of Multiple Sequence Alignments which is well known in other fields such as evolutionary biology and historical linguistics. In this paper, we present the specific problems which arise when aligning inflected forms, provide a simple alignment format, define evaluation measures and compare two implemented methods on 13 inflectional lexicons. Our intent is to provide the conditions for the inter-operability of future systems, and for incre-mental improvements in this fundamental step for quantitative morphology.

Analogy has returned to prominence in the field of inflectional morphology as a basis for new explanations of inflectional productivity. Here we review the rising profile of analogy, identifying key theoretical and methodological developments, areas of success, and priorities for future work. In morphological theory, work within so-called abstractive approaches places analogy at the center of productive processes, though significant conceptual and technical details remain to be settled. The computational modeling of inflectional analogy has a rich and diverse history, and attention is now increasingly directed to understanding inflectional systems through their internal complexity and cross-linguistic diversity. A tension exists between the prima facie promise of analogy to lead to new explanations and its relative lack of theoretical articulation. We bring this to light as we examine questions regarding inflectional defectiveness and whether analogy is reducible to grammar optimization resulting from simplicity biases in learning and language use. Expected final online publication date for the Annual Review of Linguistics, Volume 10 is January 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Dynamic models of paradigm change can elucidate how the simplest of processes may lead to unexpected outcomes, and thereby can reveal new potential explanations for observed linguistic phenomena. Ackerman & Malouf (2015) present a model in which inflectional systems reduce in disorder through the action of an attraction-only dynamic, in which lexemes only ever grow more similar to one another over time. Here we emphasise that: (1) Attraction-only models cannot evolve the structured diversity which characterises true inflectional systems, because they inevitably remove all variation; and (2) Models with both attraction and repulsion enable the emergence of systems that are strikingly reminiscent of morphomic structure such as inflection classes. Thus, just one small ingredient -- change based on dissimilarity -- separates models that tend inexorably to uniformity, and which therefore are implausible for inflectional morphology, from those which evolve stable, morphome-like structure. These models have the potential to alter how we attempt to account for morphological complexity.

Cultural attractors enable evolving cultural traits to gain the stability that underpins cumulative cultural evolution, yet the conditions that support their existence are poorly understood. We examine conditions affecting the stability of a salient kind of complex cultural attractor in human language, known as inflectional classes. We present a model of the evolution of inflectional classes, as they are reconstructed across generations via a combination of direct transmission and analogical inference. Parameters examined pertain to diversity of the lexicon and the cog-nitive policies governing inferential reasoning. We discover that persistence of stable inflection classes interacts in complex ways with features which affect how inflection classes are inferred. Thus we contribute to a greater understanding of factors affecting cultural attractors' existence, and to insights into a widespread and complex trait of human language.