2013/12/01 by Benjamin Caulfield, Caulfield, Benjamin
Computer Science · #FOS: Computer and information sciences #Formal Languages and Automata Theory (cs.FL) #cs.FL
paper · pdf · doi:10.48550/arxiv.1312.0175
Submitted to Information Processing Letters Certain proofs were not considered rigorous enough for publication
arxiv created 2014/08/23 · arxiv updated 2014/08/26
This paper presents a restricted form of linear indexed grammars, called even linear indexed grammars, which yield the even linear indexed languages. These languages properly contain the context-free languages and are contained in the set of linear indexed languages. We show that several patterns found in natural languages are also generated by these grammars, including crossing dependencies, copying, and multiple agreements. We discuss the learning problem for even linear indexed languages and show that it is reducible to that of the context-free languages. The closure properties for this class of languages are also presented.