next up previous contents
Next: Symbolic transcription system Up: Recommendation for a minimal Previous: Recommendation for a minimal

Recommendations for the orthographic representation of spoken texts

 

As defined in 2.5.1the orthographic representation of the text corresponds to a representation of the speakers utterances using the standard spelling of a given language (i.e., a transliteration). This level of representation is thus common to spoken and written corpora, and consequently conventions for orthographic representation have been developed both in corpus linguistics and in speech research.

Three representative proposals will be reviewed here and will form the basis of a set of recommendations: the NERC conventions, the SpeechDat guidelines and the EAGLES Spoken Language Working Group recommendations.

Within the tradition of corpus linguistics, the NERC initiative has adopted the conventions for orthographic transcription proposed by French (1992:3ff). They are mainly intended for the transcription of the spoken materials present in the type of reference corpora considered within the project. These recommendations can be summarized for English as follows:

These conventions can be compared with the ones developed by Boves & den Os (1995) and adopted for the transcription of the SpeechDat spoken corpora in different languages (more information on SpeechDat can be found at URL http://www.icp.grenet.fr/SpeechDat/home.html). They are based on the ones used by the LDC/ARPA (Linguistic Data Consortium/Advanced Research Projects Agency) for the production of the ATIS (Air Travel Information System) corpus,and are specially conceived for the transcription of a corpus aimed at training and assessing speech recognition systems over the telephone. Other proposals also oriented towards the transcription of speech corpora for phonetic research and speech technology have been developed, for example, within the German VERBMOBIL project (Kohleret al.1994; Hess et al., 1995; more information on the project is found at URL http://www.dfki.uni-sb.de/verbmobil/overview-us.html and at URL http://www.ims.uni-stuttgart.de/projekte/verbmobil/index-en.html), for the transcription of the HCRC Map Task corpus (Anderson et al.,1991; and more information at URL http://www.cogsci.ed.ac.uk/elsnet/ Resources/Map-Task/mt_corpus.html) or for the transcription of spontaneous spoken dialogues (Fink et al., 1995).

The most relevant SpeechDat conventions for the purpose of the present recommendations are summarised below (Boves & den Os, 1995):

Recommendations for the orthographic representation are also provided in the chapter devoted to corpus representation of the EAGLES Handbook on Spoken Language Systems (EAGLES Spoken Language Working Group, 1995). The following conventions are discussed:

The general philosophy behind the proposals put forward by the Spoken Language Working Group is that standard spelling should be used as much as possible and that all non-standard forms used in the transcription should be clearly documented. It is also proposed to generate a list of words and word forms, so that

the graphemic forms of the words can be converted to phonemes by means of computerised grapheme-to-phoneme conversion. The result of this is a list of citation forms, also called canonical forms. This forms indicate the pronunciation of words when spoken in isolation. (EAGLES Spoken Language Working Group, 1995)

The consistent use of standard spelling forms ensures then the possibility of linking levels S1 and S2 previously described in 2.5.1.

Taking into account this three proposals a set of general recommendations for the orthographic transcription of spoken materials - either read or spontaneous - can be proposed:

These recommendations are of a very general nature and constitute basic principles to be applied to the transcription of spoken materials. One aspect which would need a more in-depth discussion is punctuation. The NERC proposal suggests to mark sentence boundaries with a full stop and a capital letter and avoids using commas within sentences, while the SpeechDat recommendations suggest not to use punctuation at all. One should be aware that in spontaneous speech the delimitation of units such as sentences is not a trivial matter, since a combination of syntactic, semantic, pragmatic and prosodic criteria is required (see, for example Schuetze-Coburn, 1991), and for this reason introducing punctuation in an orthographic transcription can be sometimes a difficult and controversial activity.



next up previous contents
Next: Symbolic transcription system Up: Recommendation for a minimal Previous: Recommendation for a minimal