Well-Nestedness Properly Subsumes Strict Derivational Minimalism

Kanazawa M, Michaelis J, Salvati S, Yoshinaka R. Well-Nestedness Properly Subsumes Strict Derivational Minimalism. In: Pogodalla S, Prost J-P, eds. Logical Aspects of Computational Linguistics (LACL 2011). Lecture Notes in Computer Science. Vol 6736. Berlin, Heidelberg: Springer; 2011: 112-128

R.: Well-nestedness properly subsumes strict derivational minimalism

Abstract. Minimalist grammars (MGs) constitute a mildly contextsensitive formalism when being equipped with a particular locality condition (LC), the shortest move condition. In this format MGs define the same class of derivable string languages as multiple context-free grammars (MCFGs). Adding another LC to MGs, the specifier island condition (SPIC), results in a proper subclass of derivable languages. It is rather straightforward to see this class is embedded within the class of languages derivable by some well-nested MCFG (MCFGwn). In this paper we show that the embedding is even proper. We partially do so adapting the methods used in [13] to characterize the separation of MCFGwn-languages from MCFG-languages by means of a “simple copying ” theorem. The separation of strict derivational minimalism from well-nested MCFGs is then characterized by means of a “simple reverse copying ” theorem. Since for MGs, well-nestedness seems to be a rather ad hoc restriction, whereas for MCFGs, this holds regarding the SPIC, our result may suggest we are concerned here with a structural difference between MGs and MCFGs which cannot immediately be overcome in a non-stipulated manner.