Morphological Cues for Lexical Semantics

Most natural language processing tasks require lexical semantic information. Automated acquisition of this information would thus increase the robustness and portability of NLP systems. This paper describes an acquisition method which makes use of fixed correspondences between derivational affixes and lexical semantic information. One advantage of this method, and of other methods that rely only on surface characteristics of language, is that the necessary input is currently available

Towards Universal Semantic Tagging

The paper proposes the task of universal semantic tagging---tagging word tokens with language-neutral, semantically informative tags. We argue that the task, with its independent nature, contributes to better semantic analysis for wide-coverage multilingual text. We present the initial version of the semantic tagset and show that (a) the tags provide semantically fine-grained information, and (b) they are suitable for cross-lingual semantic parsing. An application of the semantic tagging in the Parallel Meaning Bank supports both of these points as the tags contribute to formal lexical semantics and their cross-lingual projection. As a part of the application, we annotate a small corpus with the semantic tags and present new baseline result for universal semantic tagging.Comment: 9 pages, International Conference on Computational Semantics (IWCS

Why swimming is just as difficult as dying for japanese learners of english

While both Japanese and English have a grammatic al form denoting the progressive, the two forms (te-iru & be+ing) interact differently with the inherent semantics of the verb to which they attach (Kindaichi, 1950; McClure, 1995; Shirai, 2000). Japanese change of state verbs are incompatible with a progressive interpretation, allowing only a resultative interpretation of V+ te-iru, while a progressive interpretation is preferred for activity predicates. English be+ing denotes a progressive interpretation regardless of the lexical semantics of the verb. The question that arises is how we can account for the fact that change of state verbs like dying can denote a progressive interpretation in English, but not in Japanese. While researchers such as Kageyama (1996) and Ogihara (1998, 1999) propose that the difference lies in the lexical semantics of the verbs themselves, others such as McClure (1995) have argued that the difference lies in the semantics of the grammatical forms, be+ing and te-iru. We present results from an experimental study of Japanese learners’ interpretation of the English progressive which provide support for McClure’s proposal. Results indicate that independent of verb type, learners had significantly more difficulty with the past progressive. We argue that knowledge of L2 semantics-syntax correspondences proceeds not on the basis of L1 lexical semantic knowledge, but on the basis of grammatical forms

Lexical typology through similarity semantics: Toward a semantic map of motion verbs

This paper discusses a multidimensional probabilistic semantic map of lexical motion verb stems based on data collected from parallel texts (viz. translations of the Gospel according to Mark) for 100 languages from all continents. The crosslinguistic diversity of lexical semantics in motion verbs is illustrated in detail for the domain of `go', `come', and `arrive' type contexts. It is argued that the theoretical bases underlying probabilistic semantic maps from exemplar data are the isomorphism hypothesis (given any two meanings and their corresponding forms in any particular language, more similar meanings are more likely to be expressed by the same form in any language), similarity semantics (similarity is more basic than identity), and exemplar semantics (exemplar meaning is more fundamental than abstract concepts)

Lexical and Derivational Meaning in Vector-Based Models of Relativisation

Sadrzadeh et al (2013) present a compositional distributional analysis of relative clauses in English in terms of the Frobenius algebraic structure of finite dimensional vector spaces. The analysis relies on distinct type assignments and lexical recipes for subject vs object relativisation. The situation for Dutch is different: because of the verb final nature of Dutch, relative clauses are ambiguous between a subject vs object relativisation reading. Using an extended version of Lambek calculus, we present a compositional distributional framework that accounts for this derivational ambiguity, and that allows us to give a single meaning recipe for the relative pronoun reconciling the Frobenius semantics with the demands of Dutch derivational syntax.Comment: 10 page version to appear in Proceedings Amsterdam Colloquium, updated with appendi

The interface of lexical semantics and conceptual structure deverbal and denominal nominalizations

Nominalizations can refer to events, instances of events or participants in an event. The particular reference is determined by the lexical semantics of the base and the suffix, and by the conceptual structure of the base. The comparison between deverbal and denominal nominalization in -ata in Italian reveals that the conceptual structure plays a crucial role in determining the reference of a nominalization. Italian nominalizations of -ata are productively derived from verbal and nominal bases. Derivations from verbal bases refer to a single event denoted by the base. Derivations from a nominal base N denote events or results corresponding to a limited number of pattems, such as a hit by N, a characteristic action of N, a period of N, a quantity that is contained in N, etc. The paper argues that the function of the suffix operates on the lexical meaning of the base, but the con~positiono f the lexical meaning of the base with the lexical meaning of the suffix is restricted by the conceptual properties of the base

Herstellung eines Phaffia rhodozyma : Stamms mit verstärkter Astaxanthin-Synthese über gezielte genetische Modifikation chemisch mutagenisierter Stämme

Ziel dieser Arbeit war es erstmals durch eine Kombination aus chemischer Mutagenese und gezielter genetischer Modifikation (hier: „metabolic engineering“) einen Phaffia-Stamm herzustellen, welcher über die Mutagenese hinaus über eine weiter verstärkte Astaxanthin-Synthese verfügt. Die von „DSM Nutritional Products“ bereitgestellten chemischen Mutanten wurden analysiert und über einen Selektionsprozess auf Pigmentstabilität und Wachstum hin optimiert, da die Stämme aus cryogenisierter Dauerkultur starke Pigmentinstabilitäten und ein verzögertes Wachstum aufwiesen. Über eine exploratorische Phase wurde die Carotinoidsynthese analysiert und festgestellt, dass in den Mutanten keine Einzelreaktionen betroffen sind, welche für die Heraufregulierung der Carotinoidsynthese in den Mutanten verantwortlich sind. Hierbei wurden Limitierungen identifiziert und diese durch Transformation von Expressionsplasmiden mit geeigneten Genen aufgehoben, um damit eine noch effizientere Metabolisierung von Astaxanthin-Vorstufen hin zu Astaxanthin zu erreichen. Eine Überexpression der Phytoensynthase/Lycopinzyklase crtYB resultierte in einem gesteigerten Carotinoidgehalt bei gleichbleibendem Astaxanthin- Anteil. Durch eine zweite Transformation mit einer Expressionskassette für die Astaxanthin-Synthase asy konnte der Carotinoidgehalt weiter gesteigert und zusätzlich eine Limitierung der Metabolisierung von Astaxanthin-Vorstufen behoben werden, sodass die Transformante nahezu alle Intermediate der Astaxanthinsynthese zu Astaxanthin metabolisieren konnte (Gassel et al. 2013). Es konnte gezeigt werden, dass auch in den Mutanten, aus Experimenten mit dem Wildtyp bekannte, Limitierungen identifiziert und ausgeglichen werden konnten