Topical advection as a baseline for corpus-based evolutionary dynamics
Andres Karjus (University of Edinburgh)
Tuesday 10 October 2017, 11:00–12:30
G32 7 George Square
Distinguishing genuine linguistic change (selection) from neutral evolution, and linguistic changes from those stemming from language-external factors (cultural drift) remains an important and interesting question in evolutionary lexical dynamics. A commonly used proxy to the popularity or selective fitness of a linguistic element is its corpus frequency. However, a number of recent works have pointed out that raw frequencies can often be misleading, as they are affected by shifting discourse topics and cultural trends of different periods. In other words, the changing frequency of some elements might simply be the result of the rise or fall of its associated topic. In this talk, I cover the basics of the topical-cultural advection model, a computationally simple method designed to control for topical drift and serve as a baseline in models of linguistic variant selection. Initial results show that the method is capable of describing a considerable amount of variability in word frequency changes over time. The talk will be accompanied by examples from diachronic corpora, a simulation of language change, and a datset on cultural evolution.