Cross-lingual Diachronic Distance: Application to Portuguese and Spanish.

The aim of this paper is to establish a corpus-based methodology for automatically measuring the cross-lingual distance between historical periods of two languages using perplexity. The corpus of both has been constructed adhoc with the closest spelling to the original representing chronologically and in a balanced way fiction and non-fiction. The methodology has been applied to two related languages, Portuguese and Spanish, and measured their diachronic distances both in original orthography and in an automatically transcribed spelling.