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In the context of a Nordic Conference on Bilingualism, it can be a rewarding task to look at issues such as language planning, policy and legislation from a perspective of the southern neighbours of the Nordic world. This paper therefore intends to point attention towards a case of societal multilingualism at the periphery of the Nordic world by dealing with recent developments in language policy and legislation with regard to the North Frisian speech community in the German Land of Schleswig-Holstein. As I will show, it is striking to what degree there are considerable differences in the discourse on minority protection and language legislation between the Nordic countries and a cultural area which may arguably be considered to be part of the Nordic fringe - and which itself occasionally takes Scandinavia as a reference point, e.g. in the recent adoption of a pan-Frisian flag modelled on the Nordic cross (Falkena 2006).
The main focus of the paper will be on the Frisian Act which was passed in the Parliament of Schleswig-Holstein in late 2004. It provides a certain legal basis for some political activities with regard to Frisian, but falls short of creating a true spirit of minority language protection and/or revitalisation. In contrast to the traditions of the German and Danish minorities along the German-Danish border and to minority protection in Northern Scandinavia (in particular to Sámi language rights), the approach chosen in the Frisian Act is extremely weak and has no connotation of long-term oriented language-planning, let alone a rights-based perspective.
The paper will then look at policy developments in the time since the Act was passed, e.g. in the Schleswig-Holstein election campaign in 2005, and on latest perceptions of the Frisian language situation in the discourse on North Frisian Policy in Schleswig-Holstein majority society. In the final part of the paper, I will discuss reasons for the differences in minority language policy discourse between Germany and the Nordic countries, and try to provide an outlook on how Frisian could benefit from its geographic proximity to the Nordic world.
Polish żeby under negation
(2021)
The paper addresses two patterns in the distribution of complement clauses headed by the complementizer żeby in Polish related to the presence of sentential negation. It is argued that żeby-clauses with an obligatory negation in the matrix clause, licensed by epistemic verbs, can be treated in terms of negative polarity, with żeby defined as an n-word. Structures with żeby-clauses and an obligatory negation in the embedded clause, licensed by verbs of fear, are argued to be an instance of negative complementation, with żeby specified as a negative complementizer. A uniform lexicalist analysis within the framework of HPSG is provided, employing tools developed to account for Negative Concord in Polish.
Im vorliegenden Beitrag soll gezeigt werden, wie Konnektoren als sprachliche Mittel zur Aktualisierung von zwei Arten konversationeller Aktivitäten eingesetzt werden können, nämlich von intersubjektiven bzw. gesprächsorganisatorischen Verfahren. Auf intersubjektive Verfahren greift ein Sprecher zurück, um in Kooperation mit seinem Gesprächspartner einen gemeinsamen Wissenshintergrund (common ground) zu schaffen. Durch gesprächsorganisatorische Verfahren greift der Sprecher in die gesprächsthematische Struktur des Interaktionsgeschehens ein. In diesem Beitrag wird die Aktualisierung dieser beiden konversationellen Verfahren am Beispiel der kommunikativen Gattung autobiographisches Interview betrachtet. Diese Gattung ist für eine solche Analyse m. E. besonders geeignet, denn sie zeichnet sich durch eine relativ scharfe Trennung der Gesprächsrollen aus, die das Nachvollziehen des Interaktionsgeschehens erleichtert. An einem autobiographischen Interview sind zwei Subjekte beteiligt: der Interviewte, der als Wissensträger gilt, und der Interviewer, der durch seine Rolle als Gesprächsleiter die Wissensvermittlung begünstigen soll. Der Interviewer ist also mit einer zweifachen Aufgabe konfrontiert, denn er muss die anfängliche Wissensasymmetrie ausgleichen und ist zugleich für die Gesprächsorganisation zuständig. Im Folgenden soll am Beispiel des Konjunktors und veranschaulicht werden, wie der Gebrauch von Konnektoren zur Bewältigung dieser beiden kommunikativen Aufgaben beitragen kann.
Automatic summarization systems usually are trained and evaluated in a particular domain with fixed data sets. When such a system is to be applied to slightly different input, labor- and cost-intensive annotations have to be created to retrain the system. We deal with this problem by providing users with a GUI which allows them to correct automatically produced imperfect summaries. The corrected summary in turn is added to the pool of training data. The performance of the system is expected to improve as it adapts to the new domain.
In this paper we present work in developing a computerized grammar for the Latin language. It demonstrates the principles and challenges in developing a grammar for a natural language in a modern grammar formalism. The grammar presented here provides a useful resource for natural language processing applications in different fields. It can be easily adopted for language learning and use in language technology for Cultural Heritage like translation applications or to support post-correction of document digitization.
Beyond the stars: exploiting free-text user reviews to improve the accuracy of movie recommendations
(2009)
In this paper we show that the extraction of opinions from free-text reviews can improve the accuracy of movie recommendations. We present three approaches to extract movie aspects as opinion targets and use them as features for the collaborative filtering. Each of these approaches requires different amounts of manual interaction. We collected a data set of reviews with corresponding ordinal (star) ratings of several thousand movies to evaluate the different features for the collaborative filtering. We employ a state-of-the-art collaborative filtering engine for the recommendations during our evaluation and compare the performance with and without using the features representing user preferences mined from the free-text reviews provided by the users. The opinion mining based features perform significantly better than the baseline, which is based on star ratings and genre information only.
We present a supervised machine learning AND system which tackles semantic similarity between publication titles by means of word embeddings. Word embeddings are integrated as external components, which keeps the model small and efficient, while allowing for easy extensibility and domain adaptation. Initial experiments show that word embeddings can improve the Recall and F score of the binary classification sub-task of AND. Results for the clustering sub-task are less clear, but also promising and overall show the feasibility of the approach.
The demo presents a minimalist, off-the-shelf AND tool which provides a fundamental AND operation, the comparison of two publications with ambiguous authors, as an easily accessible HTTP interface. The tool implements this operation using standard AND functionality, but puts particular emphasis on advanced methods from natural language processing (NLP) for comparing publication title semantics.
Lexical resources are often represented in table form, e. g., in relational databases, or represented in specially marked up texts, for example, in document based XML models. This paper describes how it is possible to model lexical structures as graphs and how this model can be used to exploit existing lexical resources and even how different types of lexical resources can be combined.
Cette contribution discute différents enjeux dégagés lors d’une étude des pratiques professionnelles plurilingues : ces enjeux ont émergé d’une analyse menée collaborativement par deux équipes de chercheurs, à Lyon et à Paris, participant au projet européen DYLAN (6e programme cadre) et élaborant ensemble l’analyse empirique d’un extrait d’une réunion de travail, enregistrée dans le cadre d’une collaboration sur un même terrain. Cette analyse est l’occasion de thématiser de manière exemplaire un certain nombre de questions surgissant de l’étude des contacts des langues dans les contextes professionnels, concernant aussi bien les enjeux épistémologiques que l'engagement du chercheur sur le terrain.
The ISOcat registry reloaded
(2012)
The linguistics community is building a metadata-based infrastructure for the description of its research data and tools. At its core is the ISOcat registry, a collaborative platform to hold a (to be standardized) set of data categories (i.e., field descriptors). Descriptors have definitions in natural language and little explicit interrelations. With the registry growing to many hundred entries, authored by many, it is becoming increasingly apparent that the rather informal definitions and their glossary-like design make it hard for users to grasp, exploit and manage the registry’s content. In this paper, we take a large subset of the ISOcat term set and reconstruct from it a tree structure following the footsteps of schema.org. Our ontological re-engineering yields a representation that gives users a hierarchical view of linguistic, metadata-related terminology. The new representation adds to the precision of all definitions by making explicit information which is only implicitly given in the ISOcat registry. It also helps uncovering and addressing potential inconsistencies in term definitions as well as gaps and redundancies in the overall ISOcat term set. The new representation can serve as a complement to the existing ISOcat model, providing additional support for authors and users in browsing, (re-)using, maintaining, and further extending the community’s terminological metadata repertoire.
This paper describes a new approach to improve the analysis and categorization of web documents using statistical methods for template based clustering as well as semantical analysis based on terminological ontologies. A domain-specific environment serves for prove of concept. In order to demonstrate the widespread practical benefit of our approach, we outline a combined mathematical and semantical framework for information retrieval on internet resources.
To reach even language users not acquainted to the use of grammars the Institut für Deutsche Sprache in Mannheim (Germany) looked for new ways to handle grammatical problems. Instead of confronting users with abstractions frequent difficulties of German grammar are introduced in form of exemplary questions like „Which form should be used or preferred: Anfang dieses Jahre or Anfang diesen Jahres? Looking through the long list of such questions even laymen may find solutions of grammatical problems they might not be able to formulate as such.
On valence-binding grammars
(1978)
The valence of a verb determines the number, and the syntactic class, of those expressions that must co-occur with it in a sentence. Definitions of "valence-term" and "valence-boundness" are provided whereby the precise conditions are formulated that a valence-binding grammar must satisfy. These conditions are exemplified in the framework of a simple categorial grammar, in which various reductions of the general notions can be carried out.
The sentiment polarity of an expression (whether it is perceived as positive, negative or neutral) can be influenced by a number of phenomena, foremost among them negation. Apart from closed-class negation words like no, not or without, negation can also be caused by so-called polarity shifters. These are content words, such as verbs, nouns or adjectives, that shift polarities in their opposite direction, e. g. abandoned in “abandoned hope” or alleviate in “alleviate pain”. Many polarity shifters can affect both positive and negative polar expressions, shifting them towards the opposing polarity. However, other shifters are restricted to a single shifting direction. Recoup shifts negative to positive in “recoup your losses”, but does not affect the positive polarity of fortune in “recoup a fortune”. Existing polarity shifter lexica only specify whether a word can, in general, cause shifting, but they do not specify when this is limited to one shifting direction. To address this issue we introduce a supervised classifier that determines the shifting direction of shifters. This classifier uses both resource-driven features, such as WordNet relations, and data-driven features like in-context polarity conflicts. Using this classifier we enhance the largest available polarity shifter lexicon.
We present a fine-grained NER annotations scheme with 30 labels and apply it to German data. Building on the OntoNotes 5.0 NER inventory, our scheme is adapted for a corpus of transcripts of biographic interviews by adding categories for AGE and LAN(guage) and also adding label classes for various numeric and temporal expressions. Applying the scheme to the spoken data as well as a collection of teaser tweets from newspaper sites, we can confirm its generality for both domains, also achieving good inter-annotator agreement. We also show empirically how our inventory relates to the well-established 4-category NER inventory by re-annotating a subset of the GermEval 2014 NER coarse-grained dataset with our fine label inventory. Finally, we use a BERT-based system to establish some baselines for NER tagging on our two new datasets. Global results in in-domain testing are quite high on the two datasets, near what was achieved for the coarse inventory on the CoNLLL2003 data. Cross-domain testing produces much lower results due to the severe domain differences.
The paper presents a discussion on the main linguistic phenomena of user-generated texts found in web and social media, and proposes a set of annotation guidelines for their treatment within the Universal Dependencies (UD) framework. Given on the one hand the increasing number of treebanks featuring user-generated content, and its somewhat inconsistent treatment in these resources on the other, the aim of this paper is twofold: (1) to provide a short, though comprehensive, overview of such treebanks - based on available literature - along with their main features and a comparative analysis of their annotation criteria, and (2) to propose a set of tentative UD-based annotation guidelines, to promote consistent treatment of the particular phenomena found in these types of texts. The main goal of this paper is to provide a common framework for those teams interested in developing similar resources in UD, thus enabling cross-linguistic consistency, which is a principle that has always been in the spirit of UD.
We present a new resource for German causal language, with annotations in context for verbs, nouns and adpositions. Our dataset includes 4,390 annotated instances for more than 150 different triggers. The annotation scheme distinguishes three different types of causal events (CONSEQUENCE, MOTIVATION, PURPOSE). We also provide annotations for semantic roles, i.e. of the cause and effect for the causal event as well as the actor and affected party, if present. In the paper, we present inter-annotator agreement scores for our dataset and discuss problems for annotating causal language. Finally, we present experiments where we frame causal annotation as a sequence labelling problem and report baseline results for the prediciton of causal arguments and for predicting different types of causation.
Interoperability in an Infrastructure Enabling Multidisciplinary Research: The case of CLARIN
(2020)
CLARIN is a European Research Infrastructure providing access to language resources and technologies for researchers in the humanities and social sciences. It supports the use and study of language data in general and aims to increase the potential for comparative research of cultural and societal phenomena across the boundaries of languages and disciplines, all in line with the European agenda for Open Science. Data infrastructures such as CLARIN have recently embarked on the emerging frameworks for the federation of infrastructural services, such as the European Open Science Cloud and the integration of services resulting from multidisciplinary collaboration in federated services for the wider domain of the social sciences and humanities (SSH). In this paper we describe the interoperability requirements that arise through the existing ambitions and the emerging frameworks. The interoperability theme will be addressed at several levels, including organisation and ecosystem, design of workflow services, data curation, performance measurement and collaboration. For each level, some concrete outcomes are described.
This paper presents experiments on sentence boundary detection in transcripts of spoken dialogues. Segmenting spoken language into sentence-like units is a challenging task, due to disfluencies, ungrammatical or fragmented structures and the lack of punctuation. In addition, one of the main bottlenecks for many NLP applications for spoken language is the small size of the training data, as the transcription and annotation of spoken language is by far more time-consuming and labour-intensive than processing written language. We therefore investigate the benefits of data expansion and transfer learning and test different ML architectures for this task. Our results show that data expansion is not straightforward and even data from the same domain does not always improve results. They also highlight the importance of modelling, i.e. of finding the best architecture and data representation for the task at hand. For the detection of boundaries in spoken language transcripts, we achieve a substantial improvement when framing the boundary detection problem as a sentence pair classification task, as compared to a sequence tagging approach.
Beyond Citations: Corpus-based Methods for Detecting the Impact of Research Outcomes on Society
(2020)
This paper proposes, implements and evaluates a novel, corpus-based approach for identifying categories indicative of the impact of research via a deductive (top-down, from theory to data) and an inductive (bottom-up, from data to theory) approach. The resulting categorization schemes differ in substance. Research outcomes are typically assessed by using bibliometric methods, such as citation counts and patterns, or alternative metrics, such as references to research in the media. Shortcomings with these methods are their inability to identify impact of research beyond academia (bibliometrics) and considering text-based impact indicators beyond those that capture attention (altmetrics). We address these limitations by leveraging a mixed-methods approach for eliciting impact categories from experts, project personnel (deductive) and texts (inductive). Using these categories, we label a corpus of project reports per category schema, and apply supervised machine learning to infer these categories from project reports. The classification results show that we can predict deductively and inductively derived impact categories with 76.39% and 78.81% accuracy (F1-score), respectively. Our approach can complement solutions from bibliometrics and scientometrics for assessing the impact of research and studying the scope and types of advancements transferred from academia to society.
The newest generation of speech technology caused a huge increase of audio-visual data nowadays being enhanced with orthographic transcripts such as in automatic subtitling in online platforms. Research data centers and archives contain a range of new and historical data, which are currently only partially transcribed and therefore only partially accessible for systematic querying. Automatic Speech Recognition (ASR) is one option of making that data accessible. This paper tests the usability of a state-of-the-art ASR-System on a historical (from the 1960s), but regionally balanced corpus of spoken German, and a relatively new corpus (from 2012) recorded in a narrow area. We observed a regional bias of the ASR-System with higher recognition scores for the north of Germany vs. lower scores for the south. A detailed analysis of the narrow region data revealed – despite relatively high ASR-confidence – some specific word errors due to a lack of regional adaptation. These findings need to be considered in decisions on further data processing and the curation of corpora, e.g. correcting transcripts or transcribing from scratch. Such geography-dependent analyses can also have the potential for ASR-development to make targeted data selection for training/adaptation and to increase the sensitivity towards varieties of pluricentric languages.
The paper discusses particular logical consistency conditions satisfied by German proposition-embedding predicates which determine the question type (external and internal whether-form as well as exhaustive and non-exhaustive wh-form), the correlate type (es- or da-correlate) as well as the impact of the correlate on the respective consistency condition. It will turn out that some consistency conditions also determine the embedding of verb second and subject-control.
This paper discusses the technological and methodological challenges in creating and sharing HAMATAC, the Hamburg Map Task Corpus. The first version of the corpus, consisting of 24 recordings with orthographic transcriptions and metadata, is publicly available. A second version featuring different types of linguistic annotation is in progress. I will describe how the various software tools and data formats of the EXMARaLDA system were used for transcription and multi-level annotation, to compile recordings and transcriptions into a corpus and manage metadata, to publish the corpus, and how they can be used for carrying out corpus queries (KWIC) and analyses. Some recurrent issues in corpus building and sharing and the interaction of technological and methodological aspects will be illustrated using HAMATAC.
The planning of a dictionary should consider both theoretical and empiric aspects, either for its macro- and microstructure: this is true also for Online Specialized Dictionaries of Linguistics. In particular the microstructure should be standardized and structured so as to fit with the primary and secondary functions of a dictionary. Unfortunately, empirical studies that investigate Online Specialized Dictionaries of Linguistics are rare, making it unclear which microstructural elements are obligatory and which are facultative. This article will present and comment upon the results of an investigation into a corpus of Online Specialized Dictionaries of Linguistics, focusing attention on these aspects and also the most important theoretical issues. An example taken from DIL, a German-Italian Online Dictionary of Linguistics, will end the article.
Die vorliegende empirische Untersuchung befasst sich mit einer Umfrage zur Wörterbuchbenutzung bei 41 Studentinnen und Studenten des Dipartimento di Filologia, Letteratura e Linguistica der Universität Pisa, dasselbe Department, an dem auch das deutsch-italienische sprachwissenschaftliche Online-Wörterbuch DIL erarbeitet worden ist (vgl. Flinz: 2011). Die schriftliche Umfrage wurde in Anlehnung an Hartmanns 5. Hypothese „An analysis of users´ needs should precede dictionary design“ (1989) durchgeführt. Die wichtigsten Ergebnisse waren von großer Bedeutung für die Gestaltung der makro- und mikrostrukturellen Eigenschaften des Fachwörterbuches. Die Ergebnisse der Untersuchung und die daraus folgenden Reflektionen werden in thematischen Kernblöcken vorgestellt.
DIL is a bilingual (German-Italian) online dictionary of linguistics. It is still under construction and contains 240 lemmas belonging to the subfield of “German as a Foreign Language”, but other subfields are in preparation. DIL is an open dictionary; participation of experts from various subfields is welcome. The dictionary is intended for a user group with different levels of knowledge, therefore it is a multifunctional dictionary. An analysis of existing dictionaries, either in their online or written form, was essential in order to make important decisions for the macro- or microstructure of DIL; the results are discussed. Criteria for the selection of entries and an example of an entry conclude the article.
We present web services implementing a workflow for transcripts of spoken language following TEI guidelines, in particular ISO 24624:2016 "Language resource management - Transcription of spoken language". The web services are available at our website and will be available via the CLARIN infrastructure, including the Virtual Language Observatory and WebLicht.
Digitale Medien haben in einer rasenden Geschwindigkeit inzwischen alle Lebensbereiche verändert. Sie greifen immer weiter in gewachsene Strukturen ein und prägen immer mehr unsere Wirtschafts-, Arbeits- und Sozialwelt, aber auch unsere private Kommunikation und unser alltägliches Leben. Ständig neue Entwicklungen stellen dabei alle Beteiligten immer wieder vor neue Herausforderungen. Damit einher geht die Notwendigkeit, sich kontinuierlich neues Wissen anzueignen. Als Schlüsselqualifikation zur Beherrschung dieser neuen Anforderungen in unserer sich ständig ändernden Gesellschaft gilt Medienkompetenz. Neben Lesen, Schreiben und Rechnen ist sie zur vierten Kulturtechnik geworden, die alle Bürgerinnen und Bürger in unserer Gesellschaft unabhängig von Alter, Geschlecht und Herkunft beherrschen sollten. Um an den aktuellen gesellschaftlichen und politischen Entwicklungen überhaupt noch teilnehmen und erwerbsfähig bleiben zu können, muss diese Kompetenz sogar beherrscht werden können. Damit wird ihre Vermittlung zum staatlichen Bildungsauftrag.
DIL ist ein deutsch-italienisches Online-Fachwörterbuch der Linguistik. Es ist ein offenes Wörterbuch und mit diesem Beitrag wird für eine mögliche Zusammenarbeit, Kollaboration plädiert. DIL ist noch im Aufbau begriffen; zur Zeit ist nur die Sektion DaF komplett veröffentlicht, auch wenn andere Sektionen in Bearbeitung sind. Die Sektion LEX (Lexikographie), die zur Veröffentlichung ansteht, wird zusammen mit den wichtigsten Eigenschaften des Wörterbuches präsentiert.
A "polyglottal" speech synthesis - modifications for a replica of Kempelen's speaking machine
(2019)
While good results have been achieved for named entity recognition (NER) in supervised settings, it remains a problem that for low resource languages and less studied domains little or no labelled data is available. As NER is a crucial preprocessing step for many natural language processing tasks, finding a way to overcome this deficit in data remains of great interest. We propose a distant supervision approach to NER that is both language and domain independent where we automatically generate labelled training data using gazetteers that we previously extracted from Wikipedia. We test our approach on English, German and Estonian data sets and contribute further by introducing several successful methods to reduce the noise in the generated training data. The tested models beat baseline systems and our results show that distant supervision can be a promising approach for NER when no labelled data is available. For the English model we also show that the distant supervision model is better at generalizing within the same domain of news texts by comparing it against a supervised model on a different test set.
Opinion holder extraction is one of the most important tasks in sentiment analysis. We will briefly outline the importance of predicates for this task and categorize them according to part of speech and according to which semantic role they select for the opinion holder. For many languages there do not exist semantic resources from which such predicates can be easily extracted. Therefore, we present alternative corpus-based methods to gain such predicates automatically, including the usage of prototypical opinion holders, i.e. common nouns, denoting for example experts or analysts, which describe particular groups of people whose profession or occupation is to form and express opinions towards specific items.
Das Konzept von Dominanz bezieht sich auf soziale Beziehungen, die entweder auf bereits etablierten Machtverhältnissen basieren oder solche herzustellen versuchen. Dominanz im Gespräch kann sich in bestimmten Interaktionseigenschaften manifestieren, z.B. in der ständigen Beanspruchung von Rederecht, der konsistenten thematischen und perspektivischen Steuerung, der Kontrolle von Partneraktivitäten oder dem Verhindern von Initiativen anderer u.ä..
Im Folgenden werde ich mich auf eine der Möglichkeiten konzentrieren, auf das Herstellen von Dominanz durch das Dominantsetzen von Perspektiven. Durch das konsistente Dominantsetzen der eigenen Perspektive auf einen thematischen Gegenstand oder Aspekte davon ist es möglich, zumindest in Bezug auf diesen Gegenstand Dominanz über die anderen Gesprächspartner zu etablieren.
In diesem Beitrag wird das Redewiedergabe-Korpus (RW-Korpus) vorgestellt, ein historisches Korpus fiktionaler und nicht-fiktionaler Texte, das eine detaillierte manuelle Annotation mit Redewiedergabeformen enthält. Das Korpus entsteht im Rahmen eines laufenden DFG-Projekts und ist noch nicht endgültig abgeschlossen, jedoch ist für Frühjahr 2019 ein Beta-Release geplant, welches der Forschungsgemeinschaft zur Verfügung gestellt wird. Das endgültige Release soll im Frühjahr 2020 erfolgen. Das RW-Korpus stellt eine neuartige Ressource für die Redewiedergabe-Forschung dar, die in dieser Detailliertheit für das Deutsche bisher nicht verfügbar ist, und kann sowohl für quantitative linguistische und literaturwissenschaftliche Untersuchungen als auch als Trainingsmaterial für maschinelles Lernen dienen.
This paper describes a rule-based approach to detect direct speech without the help of any quotation markers. As datasets fictional and non-fictional texts were used. Our evaluation shows that the results appear stable throughout different datasets in the fictional domain and are comparable to the results achieved in related work.
Graphenbasierte Ansätze spielen in der digitalen Lexikografie eine immer stärkere Rolle. Essentiell für die Erstellung, Verwaltung und Nutzung graphenbasierter lexikografischer Ressourcen ist jedoch eine leistungsfähige und zugleich einfach zu handhabende Zugriffsstruktur, die Suchen nach komplexen Konstellationen in solchen Graphen ermöglicht. Für heutige Graphendatenbanken stehen zahlreiche Abfragesprachen zur Verfügung, deren Verwendung jedoch verhältnismäßig voraussetzungsreich ist.
Das Poster stellt einen webbasierten, frei konfigurierbaren Query Builder vor, der die Formulierung semantisch sehr komplexer Suchabfragen an eine (mit dem Tinkerpop-Standard kompatible) Property-Graphendatenbank ermöglicht. Die Abfrage erfolgt durch einfaches visuell-interaktives Zusammenstellen hierarchisch angeordneter Abfrageelemente und liefert Antworten in Echtzeit. Dabei wird von den Komplexitäten der verwendeten Low-level-Abfragesprache Gremlin abstrahiert. Der Query Builder ist ein zentrales Modul eines derzeit entwickelten Open-Source-Softwaresystems zur Verwaltung und Online-Publikation graph-erweiterter lexikografischer Ressourcen.
We explore the feasibility of contextual healthiness classification of food items. We present a detailed analysis of the linguistic phenomena that need to be taken into consideration for this task based on a specially annotated corpus extracted from web forum entries. For automatic classification, we compare a supervised classifier and rule-based classification. Beyond linguistically motivated features that include sentiment information we also consider the prior healthiness of food items.
One problem of data-driven answer extraction in open-domain factoid question answering is that the class distribution of labeled training data is fairly imbalanced. In an ordinary training set, there are far more incorrect answers than correct answers. The class-imbalance is, thus, inherent to the classification task. It has a deteriorating effect on the performance of classifiers trained by standard machine learning algorithms. They usually have a heavy bias towards the majority class, i.e. the class which occurs most often in the training set. In this paper, we propose a method to tackle class imbalance by applying some form of cost-sensitive learning which is preferable to sampling. We present a simple but effective way of estimating the misclassification costs on the basis of class distribution. This approach offers three benefits. Firstly, it maintains the distribution of the classes of the labeled training data. Secondly, this form of meta-learning can be applied to a wide range of common learning algorithms. Thirdly, this approach can be easily implemented with the help of state-of-the-art machine learning software.
In recent years, text classification in sentiment analysis has mostly focused on two types of classification, the distinction between objective and subjective text, i.e. subjectivity detection, and the distinction between positive and negative subjective text, i.e. polarity classification. So far, there has been little work examining the distinction between definite polar subjectivity and indefinite polar subjectivity. While the former are utterances which can be categorized as either positive or negative, the latter cannot be categorized as either of these two categories. This paper presents a small set of domain independent features to detect indefinite polar sentences. The features reflect the linguistic structure underlying these types of utterances. We give evidence for the effectiveness of these features by incorporating them into an unsupervised rule-based classifier for sentence-level analysis and compare its performance with supervised machine learning classifiers, i.e. Support Vector Machines (SVMs) and Nearest Neighbor Classifier (kNN). The data used for the experiments are web-reviews collected from three different domains.
In this paper, we investigate the role of predicates in opinion holder extraction. We will examine the shape of these predicates, investigate what relationship they bear towards opinion holders, determine what resources are potentially useful for acquiring them, and point out limitations of an opinion holder extraction system based on these predicates. For this study, we will carry out an evaluation on a corpus annotated with opinion holders. Our insights are, in particular, important for situations in which no labelled training data are available and only rule-based methods can be applied.
In this paper, we compare three different generalization methods for in-domain and cross-domain opinion holder extraction being simple unsupervised word clustering, an induction method inspired by distant supervision and the usage of lexical resources. The generalization methods are incorporated into diverse classifiers. We show that generalization causes significant improvements and that the impact of improvement depends on the type of classifier and on how much training and test data differ from each other. We also address the less common case of opinion holders being realized in patient position and suggest approaches including a novel (linguistically-informed) extraction method how to detect those opinion holders without labeled training data as standard datasets contain too few instances of this type.
We present the German Sentiment Analysis Shared Task (GESTALT) which consists of two main tasks: Source, Subjective Expression and Target Extraction from Political Speeches (STEPS) and Subjective Phrase and Aspect Extraction from Product Reviews (StAR). Both tasks focused on fine-grained sentiment analysis, extracting aspects and targets with their associated subjective expressions in the German language. STEPS focused on political discussions from a corpus of speeches in the Swiss parliament. StAR fostered the analysis of product reviews as they are available from the website Amazon.de. Each shared task led to one participating submission, providing baselines for future editions of this task and highlighting specific challenges. The shared task homepage can be found at https://sites.google.com/site/iggsasharedtask/.
We present an experimental approach to determining natural dimensions of story comparison. The results show that untrained test subjects generally do not privilege structural information. When asked to justify sameness ratings, they may refer to content, but when asked to state differences, they mostly refer to style, concrete events, details and motifs. We conclude that adequate formal models of narratives must represent such non-structural data.