Ewan Klein

Integrating Know-How into the Linked Data Cloud

This paper presents the first framework for integrating procedural knowledge, or “know-how”, into the Linked Data Cloud. Know-how available on the Web, such as step-by-step instructions, is largely unstructured and isolated from other sources of online knowledge. To overcome these limitations, we propose extending to procedural knowledge the benefits that Linked Data has already brought to representing, retrieving and reusing declarative knowledge. We describe a framework for representing generic know-how as Linked Data and for automatically acquiring this representation from existing resources on the Web. This system also allows the automatic generation of links between different know-how resources, and between those resources and other online knowledge bases, such as DBpedia. We discuss the results of applying this framework to a real-world scenario and we show how it outperforms existing manual community-driven integration efforts.

Mobile robot programming using natural language

Abstract How will naive users program domestic robots? This paper describes the design of a practical system that uses natural language to teach a vision-based robot how to navigate in a miniature town. To enable unconstrained speech the robot is provided with a set of primitive procedures derived from a corpus of route instructions. When the user refers to a route that is not known to the robot, the system will learn it by combining primitives as instructed by the user. This paper describes the components of the Instruction-Based Learning architecture and discusses issues of knowledge representation, the selection of primitives and the conversion of natural language into robot-understandable procedures.

A shallow model of backchannel continuers in spoken dialogue

Spoken dialogue systems would be more acceptable if they were able to produce backchannel continuers such as mm-hmm in naturalistic locations during the users utterances. Using the HCRC Map Task Corpus as our data source, we describe models for predicting these locations using only limited processing and features of the users speech that are commonly available, and which therefore could be used as a low-cost improvement for current systems. The baseline model inserts continuers after a predetermined number of words. One further model correlates back-channel continuers with pause duration, while a second predicts their occurrence using trigram POS frequencies. Combining these two models gives the best results.

Assisted Curation: Does Text Mining Really Help?

Although text mining shows considerable promise as a tool for supporting the curation of biomedical text, there is little concrete evidence as to its effectiveness. We report on three experiments measuring the extent to which curation can be speeded up with assistance from Natural Language Processing (NLP), together with subjective feedback from curators on the usability of a curation tool that integrates NLP hypotheses for protein-protein interactions (PPIs). In our curation scenario, we found that a maximum speed-up of 1/3 in curation time can be expected if NLP output is perfectly accurate. The preference of one curator for consistent NLP output and output with high recall needs to be confirmed in a larger study with several curators.

Talking to Godot: dialogue with a mobile robot

Godot is a mobile robot platform that serves as a testbed for the interface between a sophisticated low-level robot navigation and a symbolic high-level spoken dialogue system. The interesting feature of this combined system is that information flows in two directions: (1) the navigation system. supplies landmark; information from the cognitive map used for the interpretation of the users utterances in the dialogue system; and (2) the semantic content of utterances analysed by the dialogue system are used to adjust probabilities about the robots position in the navigation system.

Coherency in children's discourse

We provide evidence that the capacity of young children to engage in social interaction exceeds that suggested by Piaget (1926). Rather than being collective monologues, the conversations between the subjects of this study (twin boys) were dialogues: the children attended to one anothers utterances and provided relevant responses. This was observed for conversations which were referentially based as well as for sound play exchanges. This is not to say that the children experienced no difficulty in sustaining cooperative discourse. It could take a speaker several turns to secure the attention of the coconversationalist and establish a discourse topic.

The interpretation of adjectival comparatives

In this paper I shall present a truth conditional semantics for simple adjectival comparatives. The leading idea is that the semantics should hug closely to the surface syntax of the construction and should not depend on postulating degrees or extents as primitive entities. The remainder of this introductory section will raise some objections to existing accounts of the semantics of comparative constructions. In Section 2 it will be argued that an adequate analysis of compared adjectives must take into account the vagueness of positive adjectives, and that the latter can be captured by interpreting degree adjectives as partial functions. Section 3 contains an analysis of degree modifiers, and in Section 4 this analysis provides the basis for the interpretation of comparatives. Section 5 spells out some consequences of the theory, while the last section contains a summary and conclusion.

Unification Categorial Grammar: a concise, extendable grammar for natural language processing

Unification Categorial Grammar (UCG) combines the syntactic insights of Categorial Grammar with the semantic insights of Discourse Representation Theory. The addition of unification to these two frameworks allows a simple account of interaction between different linguistic levels within a constraining, monostraial theory. The resulting, computationally efficient, system provides an explicit formal framework for linguistic description, within which large fragments of grammars for French and English have already been developed. We present the formal basis of UCG, with independent definitions of well-formedness for syntactic and semantic dimensions. We will also focus on the concept of modifier within the theory.

Discourse, anaphora and parsing

Discourse Representation Theory, as formulated by Hans Kamp and others, provides a model of inter- and intra-sentential anaphoric dependencies in natural language. In this paper, we present a reformulation of the model which, unlike Kamps, is specified declaratively. Moreover, it uses the same rule formalism for building both syntactic and semantic structures. The model has been implemented in an extension of PROLOG, and runs on a VAX 11/750 computer.

Meaningful conversation with a mobile robot

We describe an implementation integrating a spoken dialogue system with a mobile robot, which the user can direct to specific locations, ask for information about its status, and supply information about its environment. The robot uses an internal map for navigation, and communicates its current orientation and accessible locations to the dialogue system using a topological map as interface.