tailieunhanh - Báo cáo khoa học: "Spontaneous Lexicon Change"

The paper argues that language change can be explained through the stochasticity observed in real-world natural language use. This thesis is demonstrated by modeling language use through language games played in an evolving population of agents. We show that the artificial languages which the agents spontaneously develop based on self-organisation, do not evolve even if the population is changing. | Spontaneous Lexicon Change Luc Steels 1 2 and Frederic Kaplan 1 3 1 Sony CSL Paris - 6 Rue Amyot 75005 Paris 2 VUB Al Lab - Brussels 3 LIP6 - 4 place Jussieu 75232 Paris cedex 05 Abstract The paper argues that language change can be explained through the stochasticity observed in real-world natural language use. This thesis is demonstrated by modeling language use through language games played in an evolving population of agents. We show that the artificial languages which the agents spontaneously develop based on self-organisation do not evolve even if the population is changing. Then we introduce stochasticity in language use and show that this leads to a constant innovation new forms and new form-meaning associations and a maintenance of variation in the population if the agents are tolerant to variation. Some of these variations overtake existing linguistic conventions particularly in changing populations thus explaining lexicon change. 1 Introduction Natural language evolution takes place at all levels of language McMahon 1994 . This is partly due to external factors such as language contact between different populations or the need to express new meanings or support new modes of interaction with language. But it is well-established that language also changes spontaneously based on an internal dynamics Labov 1994 . For example many sound changes like from b to p d to t and g to k which took place in the evolution from proto-Indo-European to Modern Germanic languages do not have an external motivation. Neither do many shifts in the expression of meanings. For example the expression of future tense in English has shifted from shall to will even though shall was perfectly suited and will meant something else namely wanting to . Similarly restructuring of the grammar occurs without any apparent reason. For example in Modern English the auxiliaries come before the main verb whereas in Old English after it he conquered be would Old English vs. he would be conquered