Towards a Linked Semantic Web: Precisely, Comprehensively and Scalably Linking Heterogeneous Data in the Semantic Web

The amount of Semantic Web data is growing rapidly today. Individual users, academic institutions and businesses have already published and are continuing to publish their data in Semantic Web standards, such as RDF and OWL. Due to the decentralized nature of the Semantic Web, the same real world entity may be described in various data sources with different ontologies and assigned syntactically distinct identifiers. Furthermore, data published by each individual publisher may not be complete. This situation makes it difficult for end users to consume the available Semantic Web data effectively. In order to facilitate data utilization and consumption in the Semantic Web, without compromising the freedom of people to publish their data, one critical problem is to appropriately interlink such heterogeneous data. This interlinking process is sometimes referred to as Entity Coreference, i.e., finding which identifiers refer to the same real world entity. In the Semantic Web, the owl:sameAs predicate is used to link two equivalent (coreferent) ontology instances. An important question is where these owl:sameAs links come from. Although manual interlinking is possible on small scales, when dealing with large-scale datasets (e.g., millions of ontology instances), automated linking becomes necessary. This dissertation summarizes contributions to several aspects of entity coreference research in the Semantic Web. First of all, by developing the EPWNG algorithm, we advance the performance of the state-of-the-art by 1% to 4%. EPWNG finds coreferent ontology instances from different data sources by comparing every pair of instances and focuses on achieving high precision and recall by appropriately collecting and utilizing instance context information domain-independently. We further propose a sampling and utility function based context pruning technique, which provides a runtime speedup factor of 30 to 75. Furthermore, we develop an on-the-fly candidate selection algorithm, P-EPWNG, that enables the coreference process to run 2 to 18 times faster than the state-of-the-art on up to 1 million instances while only making a small sacrifice in the coreference F1-scores. This is achieved by utilizing the matching histories of the instances to prune instance pairs that are not likely to be coreferent. We also propose Offline, another candidate selection algorithm, that not only provides similar runtime speedup to P-EPWNG but also helps to achieve higher candidate selection and coreference F1-scores due to its more accurate filtering of true negatives. Different from P-EPWNG, Offline pre-selects candidate pairs by only comparing their partial context information that is selected in an unsupervised, automatic and domain-independent manner.In order to be able to handle really heterogeneous datasets, a mechanism for automatically determining predicate comparability is proposed. Combing this property matching approach with EPWNG and Offline, our system outperforms state-of-the-art algorithms on the 2012 Billion Triples Challenge dataset on up to 2 million instances for both coreference F1-score and runtime. An interesting project, where we apply the EPWNG algorithm for assisting cervical cancer screening, is discussed in detail. By applying our algorithm to a combination of different patient clinical test results and biographic information, we achieve higher accuracy compared to its ablations. We end this dissertation with the discussion of promising and challenging future work

Geospatial Analysis and Modeling of Textual Descriptions of Pre-modern Geography

Textual descriptions of pre-modern geography offer a different view of classical geography. The descriptions have been produced when none of the modern geographical concepts and tools were available. In this dissertation, we study pre-modern geography by primarily finding the existing structures of the descriptions and different cases of geographical data. We first explain four major geographical cases in pre-modern Arabic sources: gazetteer, administrative hierarchies, routes, and toponyms associated with people. Focusing on hierarchical divisions and routes, we offer approaches for manual annotation of administrative hierarchies and route sections as well as a semi-automated toponyms annotation. The latter starts with a fuzzy search of toponyms from an authority list and applies two different extrapolation models to infer true or false values, based on the context, for disambiguating the automatically annotated toponyms. Having the annotated data, we introduce mathematical models to shape and visualize regions based on the description of administrative hierarchies. Moreover, we offer models for comparing hierarchical divisions and route networks from different sources. We also suggest approaches to approximate geographical coordinates for places that do not have geographical coordinates - we call them unknown places - which is a major issue in visualization of pre-modern places on map. The final chapter of the dissertation introduces the new version of al-Ṯurayyā, a gazetteer and a spatial model of the classical Islamic world using georeferenced data of a pre-modern atlas with more than 2, 000 toponyms and routes. It offers search, path finding, and flood network functionalities as well as visualizations of regions using one of the models that we describe for regions. However the gazetteer is designed using the classical Islamic world data, the spatial model and features can be used for similarly prepared datasets.:1 Introduction 1 2 Related Work 8 2.1 GIS 8 2.2 NLP, Georeferencing, Geoparsing, Annotation 10 2.3 Gazetteer 15 2.4 Modeling 17 3 Classical Geographical Cases 20 3.1 Gazetteer 21 3.2 Routes and Travelogues 22 3.3 Administrative Hierarchy 24 3.4 Geographical Aspects of Biographical Data 25 4 Annotation and Extraction 27 4.1 Annotation 29 4.1.1 Manual Annotation of Geographical Texts 29 4.1.1.1 Administrative Hierarchy 30 4.1.1.2 Routes and Travelogues 32 4.1.2 Semi-Automatic Toponym Annotation 34 4.1.2.1 The Annotation Process 35 4.1.2.2 Extrapolation Models 37 4.1.2.2.1 Frequency of Toponymic N-grams 37 4.1.2.2.2 Co-occurrence Frequencies 38 4.1.2.2.3 A Supervised ML Approach 40 4.1.2.3 Summary 45 4.2 Data Extraction and Structures 45 4.2.1 Administrative Hierarchy 45 4.2.2 Routes and Distances 49 5 Modeling Geographical Data 51 5.1 Mathematical Models for Administrative Hierarchies 52 5.1.1 Sample Data 53 5.1.2 Quadtree 56 5.1.3 Voronoi Diagram 58 5.1.4 Voronoi Clippings 62 5.1.4.1 Convex Hull 62 5.1.4.2 Concave Hull 63 5.1.5 Convex Hulls 65 5.1.6 Concave Hulls 67 5.1.7 Route Network 69 5.1.8 Summary of Models for Administrative Hierarchy 69 5.2 Comparison Models 71 5.2.1 Hierarchical Data 71 5.2.1.1 Test Data 73 5.2.2 Route Networks 76 5.2.2.1 Post-processing 81 5.2.2.2 Applications 82 5.3 Unknown Places 84 6 Al-Ṯurayyā 89 6.1 Introducing al-Ṯurayyā 90 6.2 Gazetteer 90 6.3 Spatial Model 91 6.3.1 Provinces and Administrative Divisions 93 6.3.2 Pathfinding and Itineraries 93 6.3.3 Flood Network 96 6.3.4 Path Alignment Tool 97 6.3.5 Data Structure 99 6.3.5.1 Places 100 6.3.5.2 Routes and Distances 100 7 Conclusions and Further Work 10

Biographical information extraction: A language-agnostic methodology for datasets and models

A thesis submitted in partial fulfilment of the requirements of the University of Wolverhampton for the degree of Doctor of Philosophy.Information extraction (IE) refers to the task of detecting and linking information contained in written texts. While it includes various subtasks, relation extraction (RE) is used to link two entities in a text via a common relation. RE can therefore be used to build linked databases of knowledge across a wide area of topics. Today, the task of RE is treated as a supervised machine learning (ML) task, where a model is trained using a specific architecture and a specific annotated dataset. These specific datasets typically aim to represent common patterns that the model is to learn, albeit at the cost of manual annotation, which can be costly and time-consuming. In addition, due to the nature of the training process, the models can be sensitive to a specific genre or topic, and are generally monolingual. It therefore stands to reason, that certain genres and topics have better models, as they are treated with a higher priority due to financial interests for instance. This in turn leads to RE models not being available to every area of research, leaving incomplete linked databases of knowledge. For instance, if the birthplace of a person is not correctly extracted, the place and the person can not be linked correctly, therefore not leaving linked databases incomplete. To address this problem, this thesis explores aspects of RE that could be adapted in ways which require little human effort, therefore making RE models more widely available. The first aspect is the annotated data. During the course of this thesis, Wikipedia and its subsidiaries are used as sources to automatically annotate sentences for RE. The dataset, which is aimed towards digital humanities (DH) and historical research, is automatically compiled by aligning sentences from Wikipedia articles with matching structured data from sources including Pantheon and Wikidata. By exploiting the structure of Wikipedia articles and robust named entity recognition (NER), information is matched with relatively high precision in order to compile annotated relation pairs for ten different relations that are important in the DH domain: birthdate, birthplace, deathdate, deathplace, occupation, parent, educated, child, sibling and other (all other relations). Furthermore, the effectiveness of the dataset is demonstrated by training a state-of-the-art neural model to classify relation pairs. For its evaluation, a manually annotated gold standard set is used. An investigation of the necessary adaptations to recreate the automatic process in a multilingual setting is also undertaken, looking specifically at English and German, for which similar neural models are trained and evaluated on a gold standard dataset. While the process is aimed here at training neural models for RE within the domain of digital humanities and history, it may be transferable to other domains

B!SON: A Tool for Open Access Journal Recommendation

Finding a suitable open access journal to publish scientific work is a complex task: Researchers have to navigate a constantly growing number of journals, institutional agreements with publishers, funders’ conditions and the risk of Predatory Publishers. To help with these challenges, we introduce a web-based journal recommendation system called B!SON. It is developed based on a systematic requirements analysis, built on open data, gives publisher-independent recommendations and works across domains. It suggests open access journals based on title, abstract and references provided by the user. The recommendation quality has been evaluated using a large test set of 10,000 articles. Development by two German scientific libraries ensures the longevity of the project

A semantic-based approach to information processing

The research reported in this thesis is centred around the development of a semantic based approach to information processing. Traditional word-based pattern matching approaches to information processing suffer from both the richness and ambiguousness of natural language. Although retrieval performances of traditional systems can be satisfactory in many situations, it is commonly held that the traditional approach has reached the peak of its potential and any substantial improvements will be very difficult to achieve, [Smea91], Word-based pattern matching retrieval systems are devoid of the semantic power necessary to either distinguish between different senses of homonyms or identity the similar meanings of related terms. Our proposed semantic information processing system was designed to tackle these problems among others, (we also wanted to allow phrasal as well as single word terms to describe concepts). Our prototype system is comprised of a WordNet derived domain independent knowledge base (KB) and a concept level semantic similarity estimator. The KB, which is rich in noun phrases, is used as a controlled vocabulary which effectively addresses many of the problems posed by ambiguities in natural language. Similarly both proposals for the semantic similarity estimator tackle issues regarding the richness of natural language and in particular the multitude of ways of expressing the same concept. A semantic based document retrieval system is developed as a means of evaluating our approach. However, many other information processing applications are discussed with particular attention directed towards the application of our approach to locating and relating information in a large scale Federated Database System (FDBS). The document retrieval evaluation application operates by obtaining KB representations of both the documents and queries and using the semantic similarity estimators as the comparison mechanism in the procedure to determine the degree of relevance of a document for a query. The construction of KB representations for documents and queries is a completely automatic procedure, and among other steps includes a sense disambiguation phase. The sense disambiguator developed for this research also represents a departure from existing approaches to sense disambiguation. In our approach four individual disambiguation mechanisms are used to individually weight different senses of ambiguous terms. This allows the possibility of there being more than one correct sense. Our evaluation mechanism employs the Wall Street Journal text corpus and a set of TREC queries along with their relevance assessments in an ovrall document retrieval application. A traditional pattern matching tPIDF system is used as a baseline system in our evaluation experiments. The results indicate firstly that our WordNet derived KB is capable of being used as a controlled vocabulary and secondly that our approaches to estimating semantic similarity operate well at their intended concept level. However, it is more difficult to arrive at conclusive interpretations of the results with regard to the application of our semantic based systems to the complex task of document retrieval. A more complete evaluation is left as a topic for future research

How Visualization Supports the Daily Work in Traditional Humanities on the Example of Visual Analysis Case Studies

Attempts to convince humanities scholars of digital approaches are met with resistance, often. The so-called Digitization Anxiety is the phenomenon that describes the fear of many traditional scientists of being replaced by digital processes. This hinders not only the progress of the scientific domains themselves – since a lot of digital potential is missing – but also makes the everyday work of researchers unnecessarily difficult. Over the past eight years, we have made various attempts to walk the tightrope between 'How can we help traditional humanities to exploit their digital potential?' and 'How can we make them understand that their expertise is not replaced by digital means, but complemented?' We will present our successful interdisciplinary collaborations: How they came about, how they developed, and the problems we encountered. In the first step, we will look at the theoretical basics, which paint a comprehensive picture of the digital humanities and introduces us to the topic of visualization. The field of visualization has shown a special ability: It manages to walk the tightrope and thus keeps digitization anxiety at bay, while not only making it easier for scholars to access their data, but also enabling entirely new research questions. After an introduction to our interdisciplinary collaborations with the Musical Instrument Museum of Leipzig University, as well as with the Bergen-Belsen Memorial, we will present a series of user scenarios that we have collected in the course of 13 publications. These show our cooperation partners solving different research tasks, which we classify using Brehmer and Munzner’s Task Classification. In this way, we show that we provide researchers with a wide range of opportunities: They can answer their traditional research questions – and in some cases verify long-standing hypotheses about the data for the first time – but also develop their own interest in previously impossible, new research questions and approaches. Finally, we conclude our insights on individual collaborative ideas with perspectives on our newest projects. These have risen from the growing interest of collaborators in the methods we deliver. For example, we get insights into the music of real virtuosos of the 20th century. The necessary music storage media can be heard for the first time through digital tools without risking damage to the old material. In addition, we can provide computer-aided analysis capabilities that help musicologists in their work. In the course of the visualization project at the Bergen-Belsen memorial, we will see that what was once a small diary project has grown into a multimodal and international project with institutions of culture and science from eight countries. This is dedicated not only to the question of preserving cultural objects from Nazi persecution contexts but also to modern ways of disseminating and processing knowledge around this context. Finally, we will compile our experience and accumulated knowledge in the form of problems and challenges at the border between computer science and traditional humanities. These will serve as preparation and assistance for future and current interested parties of such interdisciplinary collaborative project

Subtitling Humour from the Perspective of Relevance Theory: The Office in Traditional Chinese

Subtitling the scenes containing humorous utterances in cinematic-televisual productions encounters a myriad of challenges, because the subtitler has to face the technical constraints that characterise the professional subtitling environment and the cultural barriers when reproducing humorous utterances for viewers inhabiting another culture. Past studies tend to explore more limited humour-related areas, which means that a more comprehensive picture of this specialised field is missing. The current research investigates the subtitling of humour, drawing on the framework of relevance theory and the British sitcom The Office, translated from English dialogue into Traditional Chinese subtitles. This research enquires into whether or not relevance theory can explain the subtitling strategies activated to deal with various humorous utterances in the sitcom, and, if so, to what extent. The English-Chinese Corpus of The Office (ECCO), which contains sample texts, media files and annotations, has been constructed to perform an empirical study. To enrich the corpus with valuable annotations, a typology of humour has been developed based on the concept of frame, and a taxonomy of subtitling strategies has also been proposed. The quantitative analysis demonstrates that the principle of relevance is the main benchmark for the choice of a subtitling micro-strategy within any given macro-strategy. With the chi-square test, it further proves the existence of a statistically significant association between humour types/frames and subtitling strategies at the global level. The qualitative analysis shows that the principle of relevance can operate in a subtle way, in which the subtitler invests more cognitive efforts to enhance the acceptability of subtitles. It also develops three levels of mutual dependency between the two variables, from strong, weak to null, to classify different examples. Overall, this study improves our understanding of humour translation and can facilitate a change in the curricula of translator training

Finding answers to definition questions on the web

Fundamentally, question answering systems are designed for automatically responding to queries posed by users in natural language. The first step in the answering process is query analysis, and its goal is to classify the query in concert with a set of pre-specified types. Traditionally, these classes include: factoid, definition, and list. Systems thereafter chose the answering method in congruence with the class recognised in this early phase. In short, this thesis focuses exclusively on strategies to tackle definition questions (e.g.\u27; Who is Ben Bernanke?"). This sort of question has become especially interesting in recent years, due to its significant number of submissions to search engines. Most advances in definition question answering have been made under the umbrella of the Text REtrieval Conference (TREC). This is, more precisely, a framework for testing systems operating on a collection of news articles. Thus, the objective of chapter one is to describe this framework along with presenting additional introductory aspects of definition question answering including: (a) how definition questions are prompted by individuals; (b) the different conceptions of definition, and thus of answers; and (c) the various metrics exploited for assessing systems. Since the inception of TREC, systems have put to the test manifold approaches to discover answers, throwing some light onto several key aspects of this problem. On this account, chapter four goes over a selection of some notable TREC systems. This selection is not aimed at completeness, but rather at highlighting the leading features of these systems. For the most part, systems benefit from knowledge bases (e.g., Wikipedia) for obtaining descriptions about the concept being defined (a.k.a. definiendum). These descriptions are thereafter projected onto the array of candidate answers as a means of discerning the correct answer. In other words, these knowledge bases play the role of annotated resources, and most systems attempt to find the answer candidates across the collection of news articles that are more similar to these descriptions. The cornerstone of this thesis is the assumption that it is plausible to devise competitive, and hopefully better, systems without the necessity of annotated resources. Although this descriptive knowledge is helpful, it is the belief of the author that they are built on two wrong premises: 1.It is arguable that senses or contexts related to the definiendum across knowledge bases are the same senses or contexts for the instances across the array of answer candidates. This observation also extends to the fact that not all descriptions within the group of putative answers are necessarily covered by knowledge bases, even though they might refer to the same contexts or senses. 2.Finding an efficient projection strategy does not necessarily entail a good procedure for discerning descriptive knowledge, because it shifts the goal of the task to a more like this set" instead of analysing whether or not each candidate bears the characteristics of a description. In other words, the coverage given by knowledge bases for a specific definiendum is not wide enough to learn all the characteristics that typify its descriptions, so that systems are capable of identifying all answers within the set of candidates. From another angle, a conventional projection methodology can be seen as a finder of lexical analogies. All in all, this thesis investigates into models that disregard this kind of annotated resource and projection strategy. In effect, it is the belief of the author that a robust technique of this sort can be integrated with traditional projection methodologies, and in this way bringing about an enhancement in performance. The major contributions of this thesis are presented in chapters five, six and seven. There are several ways of understanding this structure. For example, chapter five presents a general framework for answering definition questions in several languages. The primary goal of this study is to design a lightweight definition question answering system operating on web-snippets and two languages: English and Spanish. The idea is to utilise web-snippets as a source of descriptive information in several languages, and the high degree of language independency is achieved by making allowances for as little linguistic knowledge as possible. To put it more precisely, this system accounts for statistical methods and a list of stop-words, as well as a set of language-dependent definition patterns. In detail, chapter five branches into two more specific studies. The first study is essentially aimed at capitalising on redundancy for detecting answers (e.g., word frequency counts across answer candidates). Although this type of feature has been widely used by TREC systems, this study focuses on its impact on different languages, and its benefits when applied to web-snippets instead of a collection of news documents. An additional motivation behind targeting web-snippets is the hope of studying systems working on more heterogenous corpora, without incurring the need of downloading full-documents. For instance, on the Internet, the number of distinct senses for the definiendum considerably increases, ergo making it necessary to consider a sense discrimination technique. For this purpose, the system presented in this chapter takes advantage of an unsupervised approach premised on Latent Semantic Analysis. Although the outcome of this study shows that sense discrimination is hard to achieve when operating solely on web snippets, it also reveals that they are a fruitful source of descriptive knowledge, and that their extraction poses exciting challenges. The second branch extends this first study by exploiting multilingual knowledge bases (i.e. Wikipedia) for ranking putative answers. Generally speaking, it makes use of word association norms deduced from sentences that match definitions patterns across Wikipedia. In order to adhere to the premise of not profiting from articles related to a specific definiendum, these sentences are anonymised by replacing the concept with a placeholder, and the word norms are learnt from all training sentences, instead of only from the Wikipedia page about the particular definiendum. The results of this study signify that this use of these resources can also be beneficial; in particular, they reveal that word association norms are a cost-efficient solution. However, the size of the corpus markedly decreases for languages different from English, thus indicating their insufficiency to design models for other languages. Later, chapter six gets more specific and deals only with the ranking of answer candidates in English. The reason for abandoning the idea of Spanish is the sparseness observed across both the redundancy from the Internet and the training material mined from Wikipedia. This sparseness is considerably greater than in the case of English, and it makes learning powerful statistical models more difficult. This chapter presents a novel way of modeling definitions grounded on n-gram language models inferred from the lexicalised dependency tree representation of the training material acquired in the study of chapter five. These models are contextual in the sense that they are built in relation to the semantic of the sentence. Generally, these semantics can be perceived as the distinct types of definienda (e.g., footballer, language, artist, disease, and tree). This study, in addition, investigates the effect of some features on these context models (i.e., named entities, and part-of-speech tags). Overall, the results obtained by this approach are encouraging, in particular in terms of increasing the accuracy of the pattern matching. However, in all likelihood, it was experimentally observed that a training corpus comprising only positive examples (descriptions) is not enough to achieve perfect accuracy, because these models cannot deduce the characteristics that typify non-descriptive content. More essential, as future work, context models give the chance to study how different contexts can be amalgamated (smoothed) in agreement with their semantic similarities in order to ameliorate the performance. Subsequently, chapter seven gets even more specific and it searches for the set of properties that can aid in discriminating descriptions from other kinds of texts. Note that this study regards all kinds of descriptions, including those mismatching definition patters. In so doing, Maximum Entropy models are constructed on top of an automatically acquired large-scale training corpus, which encompasses descriptions from Wikipedia and non-descriptions from the Internet. Roughly speaking, different models are constructed as a means of studying the impact of assorted properties: surface, named entities, part-of-speech tags, chunks, and more interestingly, attributes derived from the lexicalised dependency graphs. In general, results corroborate the efficiency of features taken from dependency graphs, especially the root node and n-gram paths. Experiments conducted on testing sets of various characteristics suggest that it is also plausible to find attributes that can port to other corpora. The second and the third are extra chapters. The former examines different strategies to trawl the Web for descriptive knowledge. In essence, this chapter touches on several strategies geared towards boosting the recall of descriptive sentences across web snippets, especially sentences that match widespread definition patterns. This is a side, but instrumental study to the core of this thesis, as it is necessary for systems targeted at the Internet to develop effective crawling techniques. On the contrary, chapter three has two goals: (a) presenting some components used by the strategies outlined in the last three chapters, this way helping to focus on key aspects of the ranking methodologies, and hence to clearly present the relevant aspects of approaches laid out in these three chapters; and (b) fleshing out some characteristics that make separating the genuine from the misleading answer candidates difficult; particularly, across sentences matching definition patterns. Chapter three is helpful for understanding part of the linguistic phenomena that the posterior chapters deal with. On a final note about the organisation of this thesis, since there is a myriad of techniques, chapter six and seven start dissecting the related work closer to each strategy. The main contribution of each chapter begins at section 6.5 and 7.6, respectively. These two sections start with a discussion and comparison between the proposed methods and the related work presented in their corresponding preceding sections. This organisation is directed at facilitating the contextualisation of the proposed approaches as there are different question answering systems with manifold characteristics.Frage-Antwort-Systeme sind im Wesentlichen dafür konzipiert, von Benutzern in natürlicher Sprache gestellte Anfragen automatisiert zu beantworten. Der erste Schritt im Beantwortungsprozess ist die Analyse der Anfrage, deren Ziel es ist, die Anfrage entsprechend einer Menge von vordefinierten Typen zu klassifizieren. Traditionell umfassen diese: Faktoid, Definition und Liste. Danach wählten die Systeme dieser frühen Phase die Antwortmethode entsprechend der zuvor erkannten Klasse. Kurz gesagt konzentriert sich diese Arbeit ausschließlich auf Strategien zur Lösung von Fragen nach Definitionen (z.B. ,,emph{Wer ist Ben Bernanke?}"). Diese Art von Anfrage ist in den letzten Jahren besonders interessant geworden, weil sie in beachtlicher Zahl bei Suchmaschinen eingeht. Die meisten Fortschritte in Bezug auf die Beantwortung von Fragen nach Definitionen wurden unter dem Dach der Text Retrieval Conference (TREC) gemacht. Das ist, genauer gesagt, ein Framework zum Testen von Systemen, die mit einer Auswahl von Zeitungsartikeln arbeiten. Daher, zielt Kapitel eins auf eine Beschreibung dieses Rahmenwerks ab, zusammen mit einer Darstellung weiterer einführender Aspekte der Beantwortung von Definitionsanfragen. Diesen schließen u.a. ein: (a) wie Definitionsanfragen von Personen gestellt werden; (b) die unterschiedlichen Begriffe von Definition und folglich auch Antworten; und (c) die unterschiedlichen Metriken, die zur Bewertung von Systemen genutzt werden. Seit Anbeginn von TREC haben Systeme vielfältige Ansätze, Antworten zu entdecken, auf die Probe gestellt und dabei eine Reihe von zentralen Aspekten dieses Problems beleuchtet. Aus diesem Grund behandelt Kapitel vier eine Auswahl einiger bekannter TREC Systeme. Diese Auswahl zielt nicht auf Vollständigkeit ab, sondern darauf, die wesentlichen Merkmale dieser Systeme hervorzuheben. Zum größten Teil nutzen die Systeme Wissensbasen (wie z.B. Wikipedia), um Beschreibungen des zu definierenden Konzeptes (auch als Definiendum bezeichnet) zu erhalten. Diese Beschreibungen werden danach auf eine Reihe von möglichen Antworten projiziert, um auf diese Art die richtige Antwort zu ermitteln. Anders ausgedrückt nehmen diese Wissensbasen die Funktion von annotierten Ressourcen ein, wobei die meisten Systeme versuchen, die Antwortkandidaten in einer Sammlung von Zeitungsartikeln zu finden, die diesen Beschreibungen ähnlicher sind. Den Grundpfeiler dieser Arbeit bildet die Annahme, dass es plausibel ist, ohne annotierte Ressourcen konkurrenzfähige, und hoffentlich bessere, Systeme zu entwickeln. Obwohl dieses deskriptive Wissen hilfreich ist, basieren sie nach Überzeugung des Autors auf zwei falschen Annahmen: 1. Es ist zweifelhaft, ob die Bedeutungen oder Kontexte, auf die sich das Definiendum bezieht, dieselben sind wie die der Instanzen in der Reihe der Antwortkandidaten. Darüber hinaus erstreckt sich diese Beobachtung auch auf die Tatsache, dass nicht alle Beschreibungen innerhalb der Gruppe der mutmaßlichen Antworten notwendigerweise von Wissensbasen abgedeckt werden, auch wenn sie sich auf dieselben Bedeutungen und Kontexte beziehen. 2. Eine effiziente Projektionsstrategie zu finden bedeutet nicht notwendigerweise auch ein gutes Verfahren zur Feststellung von deskriptivem Wissen, denn es verschiebt die Zielsetzung der Aufgabe hin zu einem ,,mehr wie diese Menge" statt zu analysieren, ob jeder Kandidat den Charakteristika einer Beschreibung entspricht oder nicht. Anders ausgedrückt ist die Abdeckung, die durch Wissensbasen für ein spezifisches Definiendum gegeben ist, nicht umfassend genug, um alle Charakteristika, die für seine Beschreibungen kennzeichnend sind, zu erlernen, so dass die Systeme in der Lage sind, alle Antworten innerhalb der Kandidatenmenge zu identifizieren. Eine konventionelle Projektionsstrategie kann aus einem anderen Blickwinkel als Prozedur zum Finden lexikalischer Analogien betrachtet werden. Insgesamt untersucht diese Arbeit Modelle, die Strategien dieser Art in Verbindung mit annotierten Ressourcen und Projektion außer Acht lassen. Tatsächlich ist es die Überzeugung des Autors, dass eine robuste Technik dieser Art mit traditionellen Methoden der Projektion integriert wird und so eine Leistungssteigerung ermöglichen kann. Die größeren Beiträge dieser Arbeit werden in den Kapiteln fünf, sechs und sieben präsentiert. Es gibt mehrere Wege diese Struktur zu verstehen. Kapitel fünf, beispielsweise, präsentiert einen allgemeinen Rahmen für die Beantwortung von Fragen nach Definitionen in mehreren Sprachen. Das primäre Ziel dieser Studie ist es, ein leichtgewichtiges System zur Beantwortung von Fragen nach Definitionen zu entwickeln, das mit Web-Snippets und zwei Sprachen arbeitet: Englisch und Spanisch. Die Grundidee ist, von Web-Snippets als Quelle deskriptiver Information in mehreren Sprachen zu profitieren, wobei der hohe Grad an Sprachunabhängigkeit dadurch erreicht wird, dass so wenig linguistisches Wissen wie möglich berücksichtigt wird. Genauer gesagt berücksichtigt dieses System statistische Methoden und eine Liste von Stop-Wörtern sowie eine Reihe von sprach-spezifischen Definitionsmustern. Im Einzelnen teilt sich Kapitel fünf in zwei spezifischere Studien auf. Die erste Studie zielt im Grunde darauf ab, aus Redundanz für die Ermittlung von Antworten Kapital zu schlagen (z.B. Worthäufigkeiten über verschiedene Antwortkandidaten hinweg). Obwohl eine solche Eigenschaft unter TREC Systemen weit verbreitet ist, legt diese Studie den Schwerpunkt auf die Auswirkungen auf verschiedene Sprachen und auf ihre Vorteile bei der Anwendung auf Web-Snippets statt Zeitungsartikeln. Eine weitere Motivation dahinter, Web-Snippets ins Auge zu fassen, ist die Hoffnung, Systeme zu studieren, die mit heterogenen Corpora arbeiten, ohne es nötig zu machen, vollständige Dokumente herunter zu laden. Im Internet, beispielsweise, steigt die Zahl verschiedener Bedeutungen für das Definiendum deutlich an, was es notwendig macht, eine Technik zur Unterscheidung von Bedeutungen in Betracht zu ziehen. Zu diesem Zweck nutzt das System, das in diesem Kapitel vorgestellt wird, einen unüberwachten Ansatz, der auf der Latent Semantic Analysis basiert. Auch wenn das Ergebnis dieser Studie zeigt, dass die Unterscheidung von Bedeutungen allein anhand von Web-Snippets schwer zu erreichen ist, so lässt es doch auch erkennen, dass sie eine fruchtbare Quelle deskriptiven Wissens darstellen und dass ihre Extraktion spannende Herausforderungen bereithält. Der zweite Teil erweitert diese erste Studie durch die Nutzung mehrsprachiger Wissensbasen (d.h. Wikipedia), um die möglichen Antworten in eine Rangfolge einzureihen. Allgemein ausgedrückt profitiert sie von Wortassoziationsnormen, die von Sätzen gelernt werden, die über Wikipedia hinweg zu Definitionsmustern passen. Um an der Prämisse festzuhalten, keine Artikel mit Bezug auf eine spezifisches Definiendum zu nutzen, werden diese Sätze anonymisiert, indem der Begriff mit einem Platzhalter ersetzt wird, und die Wortnormen werden von allen Sätzen der Trainingsmenge gelernt, statt nur von dem Wikipedia-Artikel, der sich auf das spezielle Definiendum bezieht. Die Ergebnisse dieser Studie zeigen, dass diese Nutzung dieser Ressourcen ebenfalls vorteilhaft sein kann; speziell zeigen sie auf, dass Wortassoziationsnormen eine kosteneffiziente Lösung darstellen. Allerdings nehmen die Corpusgrößen über andere Sprachen als Englisch deutlich ab, was auf deren Unzulänglichkeit für die Konstruktion von Modellen für andere Sprachen hinweist. Kapitel sechs, weiter hinten, wird spezieller und handelt ausschließlich von der Einordnung von Antwortkandidaten in englischer Sprache in eine Rangfolge. Der Grund dafür, hier Spanisch außer Acht zu lassen, ist die geringe beobachtete Dichte, sowohl in Bezug auf redundante Information im Internet als auch in Bezug auf Trainingsmaterial, das von Wikipedia erworben wurde. Diese geringe Dichte ist deutlich stärker ausgeprägt als im Fall der englischen Sprache und erschwert das Erlernen mächtiger statischer Modelle. Dieses Kapitel präsentiert einen neuartigen Weg, Definitionen zu modellieren, die in n-gram Sprachmodellen verankert sind, die aus der lexikalisierten Darstellung des Abhängigkeitsbaumes des in Kapitel fünf erworbenen Trainingsmaterials gelernt wurden. Diese Modelle sind kontextuell in dem Sinne, dass sie in Bezug auf die Semantikdes Satzes konstruiert werden. Im Allgemeinen können diese Semantiken als unterschiedliche Typen von Definienda betrachtet werden (z.B. Fußballer, Sprache, Künstler, Krankheit und Baum). Diese Studie untersucht zusätzlich die Auswirkungen einiger Eigenschaften (nämlich benannter Entitäten und Part-of-speech-Tags) auf diese Kontextmodelle. Insgesamt sind die Ergebnisse, die mit diesem Ansatz erhalten wurden, ermutigend, insbesondere in Bezug auf eine Steigerung der Genauigkeit des Musterabgleichs. Indes wurde höchstwahrscheinlich experimentell beobachtet, dass ein Trainingscorpus, das nur Positivbeispiele (Beschreibungen) enthält, nicht ausreicht, um perfekte Genauigkeit zu erreichen, da diese Modelle die Charakteristika nicht ableiten können, die für nicht-deskriptiven Inhalt kennzeichnend sind. Für die weitere Arbeit ermöglichen es Kontextmodelle zu untersuchen, wie unterschiedliche Kontexte in Übereinstimmung mit deren semantischen Ähnlichkeiten verschmolzen (geglättet) werden können, um die Leistung zu verstärken. Kapitel sieben wird anschließend sogar noch spezieller und sucht nach der Menge von Eigenschaften, die dabei helfen kann, Beschreibungen von anderen Textarten zu unterscheiden. Dabei sollte beachtet werden, dass diese Studie alle Arten von Beschreibungen berücksichtigt, einschließlich derer, die Definitionsmustern nicht genügen. Dadurch werden Maximum-Entropy-Modelle konstruiert, die auf einen automatisch akquirierten Corpus von großem Umfang aufsetzen, der Beschreibungen von Wikipedia und Nicht-Beschreibungen aus dem Internet umfasst. Grob gesagt werden unterschiedliche Modelle konstruiert, um die Auswirkungen verschiedenerlei Merkmale zu untersuchen: Oberfläche, benannte Entitäten, Part-of-speech-Tags, Chunks und, noch interessanter, von den lexikalisierten Abhängigkeitsgraphen abgeleitete Attribute. Im Allgemeinen bestätigen die Ergebnisse die Effizienz von Merkmalen, die Abhängigkeitsgraphen entnommen sind, insbesondere Wurzelknoten und n-gram-Pfaden. Experimente, die mit verschiedenen Testmengen diverser Charakteristika durchgeführt wurden, legen nahe, dass auch angenommen werden kann, dass Attribute gefunden werden, die sich auf andere Corpora übertragen lassen. Es gibt zwei weitere Kapitel: zwei und drei. Ersteres untersucht unterschiedliche Strategien, das Netz nach deskriptivem Wissen zu durchforsten. Im Wesentlichen analysiert dieses Kapitel einige Strategien, die darauf abzielen, die Trefferquote (den Recall) deskriptiver Sätze

Study on open science: The general state of the play in Open Science principles and practices at European life sciences institutes

Nowadays, open science is a hot topic on all levels and also is one of the priorities of the European Research Area. Components that are commonly associated with open science are open access, open data, open methodology, open source, open peer review, open science policies and citizen science. Open science may a great potential to connect and influence the practices of researchers, funding institutions and the public. In this paper, we evaluate the level of openness based on public surveys at four European life sciences institute