Automatic identification of discourse markers in dialogues: An in-depth study of like and well

The lexical items like and well can serve as discourse markers (DMs), but can also play numerous other roles, such as verb or adverb. Identifying the occurrences that function as DMs is an important step for language understanding by computers. In this study, automatic classifiers using lexical, prosodic/positional and sociolinguistic features are trained over transcribed dialogues, manually annotated with DM information. The resulting classifiers improve state-of-the-art performance of DM identification, at about 90% recall and 79% precision for like (84.5% accuracy, κ = 0.69), and 99% recall and 98% precision for well (97.5% accuracy, κ = 0.88). Automatic feature analysis shows that lexical collocations are the most reliable indicators, followed by prosodic/positional features, while sociolinguistic features are marginally useful for the identification of DM like and not useful for well. The differentiated processing of each type of DM improves classification accuracy, suggesting that these types should be treated individually.

Annotating the meaning of discourse connectives in multilingual corpora

Discourse connectives are lexical items indicating coherence relations between discourse segments. Even though many languages possess a whole range of connectives, important divergences exist cross-linguistically in the number of connectives that are used to express a given relation. For this reason, connectives are not easily paired with a univocal translation equivalent across languages. This paper is a first attempt to design a reliable method to annotate the meaning of discourse connectives cross-linguistically using corpus data. We present the methodological choices made to reach this aim and report three annotation experiments using the framework of the Penn Discourse Tree Bank.

Towards Automatic Identification of Discourse Markers in Dialogs: the Case of 'Like'

This article discusses the detection of discourse markers (DM) in dialog transcriptions, by human annotators and by automated means. After a theoretical discussion of the definition of DMs and their relevance to natural language processing, we focus on the role of like as a DM. Results from experiments with human annotators show that detection of DMs is a difficult but reliable task, which requires prosodic information from soundtracks. Then, several types of features are defined for automatic disambiguation of like: collocations, part-of-speech tags and duration-based features. Decision-tree learning shows that for like, nearly 70% precision can be reached, with near 100% recall, mainly using collocation filters. Similar results hold for well, with about 91% precision at 100% recall.

The phylogeny of closely related species as revealed by the genealogy of a speciation gene, Odysseus

Molecular differentiation between races or closely related species is often incongruent with the reproductive divergence of the taxa of interest. Shared ancient polymorphism and/or introgression during secondary contact may be responsible for the incongruence. At loci contributing to speciation, these two complications should be minimized (1, 2); hence, their variation may more faithfully reflect the history of the species' reproductive differentiation. In this study, we analyzed DNA polymorphism at the Odysseus (OdsH) locus of hybrid sterility between Drosophila mauritiana and Drosophila simulans and were able to verify such a prediction. Interestingly, DNA variation only a short distance away (1.8 kb) appears not to be influenced by the forces that shape the recent evolution of the OdsH coding region. This locus thus may represent a test case of inferring phylogeny of very closely related species.

Our Campbell ancestors, 1742-1937. Traditions and history of the family of five Campbell brothers and sisters; John, James Douglas, Hester, Mary and Samuel: including what is known of them in New Jersey; York county, Pennsylvania; Union county, South Carolina and in Ohio. A genealogy of the known descendants of John Campbell through his son James, and Samuel Campbell through his son Ralph, also brief ancestral notes on families connected by marriage with the foregoing; viz; Parnell, Clark, Spray, Wilson, Haskett, Mendenhall and Underhill,

Bibliographical foot-notes.

Genealogy of the Greely-Greeley family,

On back of cover: Greele, Greely, Greeley.