Speech recognition is the task of converting an acoustic signal, which contains speech, to written text. The error of a speech recognition system is measured in the number of words in which the recognized and the spoken text differ. This work investigates and develops decoding and system combination approaches within the Bayes risk decoding framework with the objective of reducing the number of...

Natural language processing for historical text imposes a variety of challenges, such as to deal with a high degree of spelling variation. Furthermore, there is often not enough linguistically annotated data available for training part-of-speech taggers and other tools aimed at handling this specific kind of text. In this paper we present a Levenshtein-based approach to normalisation of histori...

Edit distance is not the only approach how distance between two character sequences can be calculated. Strings can be also compared in somewhat subtler geometric ways. A procedure inspired by Random Indexing can attribute an D-dimensional geometric coordinate to any character N-gram present in the corpus and can subsequently represent the word as a sum of N-gram fragments which the string conta...

RÉSUMÉ. Nous proposons des algorithmes dédiés à l'indexation et à la recherche approximative d'information dans les bases de données hétérogènes semi-structurées XML. Le modèle d'indexation proposé est adapté à la recherche de contenu textuel dans les contextes XML définis par les structures d'arbres. Les mécanismes de recherche approchée mis en œuvre s’appuient sur une distance de Levenshtein ...

There is currently an abundance of vision algorithms which, provided with a sequence of images that have been acquired from sufficiently close successive 3D locations, are capable of determining the relative positions of the viewpoints from which the images have been captured. However, very few of these algorithms can cope with unordered image sets. This paper presents an efficient method for r...

So far, there has not been a comparative evaluation of different approaches for text extraction from scholarly figures. In order to fill this gap, we have defined a generic pipeline for text extraction that abstracts from the existing approaches as documented in the literature. In this paper, we use this generic pipeline to systematically evaluate and compare 32 configurations for text extracti...

In this paper, we consider a recent technique of Levenshtein [9] which was introduced to prove improved lower bounds on aperiodic correlation of sequence families over the complex roots of unity. We first give a new proof of the Welch [12] lower bound on the periodic correlation of complex roots of unity sequences using a modification of Levenshtein’s technique. This improves the Welch lower bo...

We have recently shown that q-gram filters based on gapped q-grams instead of the usual contiguous q-grams can provide orders of magnitude faster and/or more efficient filtering for the Hamming distance. In this paper, we extend the results for the Levenshtein distance, which is more problematic for gapped q-grams because an insertion or deletion in a gap affects a q-gram while a replacement do...

The work in this thesis has been carried out under the auspices of the Behavioral and Cognitive Neurosciences (BCN) research school, Groningen. Acknowledgements This thesis is attributed to exactly one author as can be seen on both the cover and the title pages. The author is the one who is responsible for the content. But it should be emphasized that many people contributed to the coming about...