Plain lists of collocations as provided to date by most approaches to automatic acquisition of collocations from corpora are useful as a resource for dictionary construction. However, their use is rather limited in the case of NLP-applications such as Text Generation, Machine Translation and Text Summarization if not enriched by information on the grammatical function of the collocation elements and by information on the semantics of the collocations as multiword units. In this article, we describe an approach to a fine-grained classification of verb-noun bigrams according to a semantically motivated typology of collocations and illustrate this with Spanish material. The typology of collocations that underlies our classification is based on verb-noun Lexical Functions (LFs) from the Explanatory Combinatorial Lexicology. In the first stage of the approach, the program learns the semantic features of each LF from training data. In the second stage, it examines the semantic features of verb-noun candidate bigrams and compares them with the features of all the LFs taken into account. A candidate whose features are sufficiently similar to those of a specific LF is considered to be an instance of this LF. The semantic features of both the training material and the candidate bigrams are derived from the hyperonymy hierarchies provided by the EuroWordNet. In the experiments carried out to validate the approach, we achieved an average $f$-score of about 70%.

With this first issue of Volume 10 of Natural Language Engineering we would like to take this opportunity to reflect on the development of the journal, especially over the last year or two, and to look forward to a number of future developments.

Every building, and every computer program, has an architecture: structural and organisational principles that underpin its design and construction. The garden shed once built by one of the authors had an ad hoc architecture, extracted (somewhat painfully) from the imagination during a slow and non-deterministic process that, luckily, resulted in a structure which keeps the rain on the outside and the mower on the inside (at least for the time being). As well as being ad hoc (i.e. not informed by analysis of similar practice or relevant science or engineering) this architecture is implicit: no explicit design was made, and no records or documentation kept of the construction process.

This paper describes the Linguistic Annotation Framework under development within ISO TC37 SC4 WG1. The Linguistic Annotation Framework is intended to serve as a basis for harmonizing existing language resources as well as developing new ones.

The new frontier of research on Information Extraction from texts is portability without any knowledge of Natural Language Processing. The market potential is very large in principle, provided that a suitable easy-to-use and effective methodology is provided. In this paper we describe LearningPinocchio, a system for adaptive Information Extraction from texts that is having good commercial and scientific success. Real world applications have been built and evaluation licenses have been released to external companies for application development. In this paper we outline the basic algorithm behind the scenes and present a number of applications developed with LearningPinocchio. Then we report about an evaluation performed by an independent company. Finally, we discuss the general suitability of this IE technology for real world applications and draw some conclusion.

This paper presents modifications to a standard probabilistic context-free grammar that enable a predictive parser to avoid garden pathing without resorting to any ad-hoc heuristic repair. The resulting parser is shown to apply efficiently to both newspaper text and telephone conversations with complete coverage and excellent accuracy. The distribution over trees is peaked enough to allow the parser to find parses efficiently, even with the much larger search space resulting from overgeneration. Empirical results are provided for both Wall St. Journal and Switchboard test corpora.

We present the RAGS (Reference Architecture for Generation Systems) framework, a specification of an abstract Natural Language Generation (NLG) system architecture to support sharing, re-use, comparison and evaluation of NLG technologies. We argue that the evidence from a survey of actual NLG systems calls for a different emphasis in a reference proposal from that seen in similar initiatives in information extraction and multimedia interfaces. We introduce the framework itself, in particular the two-level data model that allows us to support the complex data requirements of NLG systems in a flexible and coherent fashion, and describe our efforts to validate the framework through a range of implementations.

We introduce a simple method to build Lexicalized Hidden Markov Models (L-HMMs) for improving the precision of part-of-speech tagging. This technique enriches the contextual Language Model taking into account a set of selected words empirically obtained. The evaluation was conducted with different lexicalization criteria on the Penn Treebank corpus using the TnT tagger. This lexicalization obtained about a 6% reduction of the tagging error, on an unseen data test, without reducing the efficiency of the system. We have also studied how the use of linguistic resources, such as dictionaries and morphological analyzers, improves the tagging performance. Furthermore, we have conducted an exhaustive experimental comparison that shows that Lexicalized HMMs yield results which are better than or similar to other state-of-the-art part-of-speech tagging approaches. Finally, we have applied Lexicalized HMMs to the Spanish corpus LexEsp.

Existing software systems for automated essay scoring can provide NLP researchers with opportunities to test certain theoretical hypotheses, including some derived from Centering Theory. In this study we employ the Educational Testing Service's e-rater essay scoring system to examine whether local discourse coherence, as defined by a measure of Centering Theory's Rough-Shift transitions, might be a significant contributor to the evaluation of essays. Rough-Shifts within students' paragraphs often occur when topics are short-lived and unconnected, and are therefore indicative of poor topic development. We show that adding the Rough-Shift based metric to the system improves its performance significantly, better approximating human scores and providing the capability of valuable instructional feedback to the student. These results indicate that Rough-Shifts do indeed capture a source of incoherence, one that has not been closely examined in the Centering literature. They not only justify Rough-Shifts as a valid transition type, but they also support the original formulation of Centering as a measure of discourse continuity even in pronominal-free text. Finally, our study design, which used a combination of automated and manual NLP techniques, highlights specific areas of NLP research and development needed for engineering practical applications.

The topic of mood and modality (MOD) is a difficult aspect of language description because, among other reasons, the inventory of modal meanings is not stable across languages, moods do not map neatly from one language to another, modality may be realised morphologically or by free-standing words, and modality interacts in complex ways with other modules of the grammar, like tense and aspect. Describing MOD is especially difficult if one attempts to develop a unified approach that not only provides cross-linguistic coverage, but is also useful in practical natural language processing systems. This article discusses an approach to MOD that was developed for and implemented in the Boas Knowledge-Elicitation (KE) system. Boas elicits knowledge about any language, L, from an informant who need not be a trained linguist. That knowledge then serves as the static resources for an L-to-English translation system. The KE methodology used throughout Boas is driven by a resident inventory of parameters, value sets, and means of their realisation for a wide range of language phenomena. MOD is one of those parameters, whose values are the inventory of attested and not yet attested moods (e.g. indicative, conditional, imperative), and whose realisations include flective morphology, agglutinating morphology, isolating morphology, words, phrases and constructions. Developing the MOD elicitation procedures for Boas amounted to wedding the extensive theoretical and descriptive research on MOD with practical approaches to guiding an untrained informant through this non-trivial task. We believe that our experience in building the MOD module of Boas offers insights not only into cross-linguistic aspects of MOD that have not previously been detailed in the natural language processing literature, but also into KE methodologies that could be applied more broadly.

Here's something I read the other day:

IVR [interactive voice response] technology is at a point now where consumers almost cannot tell the difference between talking to a person and talking to a computer.

Generic software architectures aim to support re-use of components, focusing of research and development effort, and evaluation and comparison of approaches. In the field of natural language processing, generic frameworks for understanding have been successfully deployed to meet all of these aims, but nothing comparable yet exists for generation. The nature of the task itself, and the current methodologies available to research it, seem to make it more difficult to reach the necessary level of consensus to support generic proposals. Recent work has made progress towards establishing a generic framework for generation at the functional level, but left open the issue of actual implementation. In this paper, we discuss the requirements for such an implementation layer for generation systems, drawing on two initial attempts to implement it. We argue that it is possible and useful to distinguish “functional architecture” from “implementation architecture” for generation systems.

If you wanted to make some money out of natural language processing, an appropriate strategy might be to identify an area of technology that was relatively mature—one where the more fundamental technical problems had been resolved through a significant amount of research activity—and then identify potential applications for that technology.

The development of large-scale dialog systems requires a flexible architecture model and adequate software support to cope with the challenge of system integration. This contributionOur current work in the context of the SmartKom project has been funded by the German Federal Ministry for Education and Research (BMBF) under grant 01 IL 905 K7. presents a general framework for building integrated natural-language and multimodal dialog systems. Our approach relies on a distributed component model that enables flexible re-use and extension of existing software modules and is able to deal with a heterogeneous software environment. A practical result of our research is the development of a sophisticated integration platform, called MULTIPLATFORM, which is based on the proposed framework. This MULTIPLATFORM testbed has been used in various large and mid-size research projects to develop integrated system prototypes.

We present the architecture and data model for TEXTRACT, a robust, scalable and configurable document analysis framework. TEXTRACT has been engineered as a pipeline architecture, allowing for rapid prototyping and application development by freely mixing reusable, existing, language analysis plugins and custom, new, plugins with customizable functionality. We discuss design issues which arise from requirements of industrial strength efficiency and scalability, and which are further constrained by plugin interactions, both among themselves, and with a common data model comprising an annotation store, document vocabulary and a lexical cache. We exemplify some of these by focusing on a meta-plugin: an interpreter for annotation-based finite state transduction, through which many linguistic filters can be implemented as stand-alone plugins. The framework and component plugins have been extensively deployed in both research and industrial environments, for a broad range of text analysis and mining tasks.

IBM Research has over 200 people working on Unstructured Information Management (UIM) technologies with a strong focus on Natural Language Processing (NLP). These researchers are engaged in activities ranging from natural language dialog, information retrieval, topic-tracking, named-entity detection, document classification and machine translation to bioinformatics and open-domain question answering. An analysis of these activities strongly suggested that improving the organization's ability to quickly discover each other's results and rapidly combine different technologies and approaches would accelerate scientific advance. Furthermore, the ability to reuse and combine results through a common architecture and a robust software framework would accelerate the transfer of research results in NLP into IBM's product platforms. Market analyses indicating a growing need to process unstructured information, specifically multilingual, natural language text, coupled with IBM Research's investment in NLP, led to the development of middleware architecture for processing unstructured information dubbed UIMA. At the heart of UIMA are powerful search capabilities and a data-driven framework for the development, composition and distributed deployment of analysis engines. In this paper we give a general introduction to UIMA focusing on the design points of its analysis engine architecture and we discuss how UIMA is helping to accelerate research and technology transfer.

In this paper we present recent work on GATE, a widely-used framework and graphical development environment for creating and deploying Language Engineering components and resources in a robust fashion. The GATE architecture has facilitated the development of a number of successful applications for various language processing tasks (such as Information Extraction, dialogue and summarisation), the building and annotation of corpora and the quantitative evaluations of LE applications. The focus of this paper is on recent developments in response to new challenges in Language Engineering: Semantic Web, integration with Information Retrieval and data mining, and the need for machine learning support.