On lexically biased discourse organization in text generation
Leo Wanner · 1994
In this paper, we show that Reileralion and Collocation relations as introduced I)y Ilalliday and llasan may function as lexieally I)iased discourse structure relations and that these relations are well represented by sequences of Mel'&flds Lexical Funclions (Ll,'s).We propose to use Lie sequences for tl,e final determination and realization of discourse organization during lexical choice in text generation. 1 LEXICAL PHENOMENA IN DIS-COURSE 1.1 The Problem In text generation, the tmsk of content selection and discourse organization, i.e. text phuming, has often been opposed to the task of linguistic realization ()1" the information selected and organized by the text planning process (el., e.g., MeKeown and Swartout, 1987).However, discourse organization is not possibh', without taking into account linguistic means that are available to express a particular meaning (el., e.g., Meteer, 1992; Rubinoff, 1992).Esl)e.eially the ['allure to integrate lexical choice into the phuming process may lead to monotonous, awkward, or even ungrammatical text (note that when used separately, the clauses in (Ix) and (2a) are fully acceptable):' (I) a. ?Alle bewahrten Ruhe; nut llans holtrite keine lbtlw/(sie nieht) ]~ew~bE,Lt!lit.'All kept cabnness; only l[ans could not keep c,~hnness/ it'.VS. b.Alle bewahrten Ruhe; nnr llans konnte nicht rnhiq blciben lit.'All kept calmness; only I lans eouhl not kee l) cahn'.(2) a.? l)er langgephmte AusJlu9 fired a,n Sonntag start; wir unternahmen ihn mit der 9anze;, 1'braille lit.'The long-pl~tnned trip took platte on Sunday; we undertook it with the entire family'. VS. b.Der hmggephmte Attsfln 9 fand ant Sonntag stalt; die (mnze l'hrnilie nahm daran teil lit.'The iong-phuumd trip took pl~tcc on Sunday; the entire family took part in it'. 1 In the following exatnples~ the inal)prol)viate lexieal expression in the (a) sentences and its IllOl'e alq)rol)riatc alternat, ive in the (b) sentences are underlined.(3) a, *lhtns muel, te clue Entdeckun9; diese Entdccktmg war wirklich lit.'ll;uts m~ule ~ discovery; this discovery was real'. VS. b. llans maehte eine lrnldeckun.q; diese lCntdeekun9 war eine I')ntdeekung i m wahrslen £'inne des I'Vorles