Corpus-based productivity measures of English -er agentives and instrumentals

Abstract

This paper investigates the claim that agentive and instrumental forms of English “-er”morpheme show differing productivity (a claim due to Derwing 1976). An attempt is made to replicate Derwing’s findings using modern corpus methods. Novel annotations for animacy and agentivity/instrumentality were created on the Brown corpus (Kučera and Francis, 1967). Findings show agentive “-er” is much more frequent than instrumental “-er” (>5× token frequency, >3× type frequency). Exponential modeling suggests the productivity of instrumental “-er” is not less than agentive “-er”, and perhaps slightly greater (contra Derwing). Agentive/instrumental annotations also reveal many difficult-to-classify cases. However, productivity values based on the agentivity/instrumentality were mirrored by those based on animate/inanimate distinctions. This parity arises from high correlation between the agentive and animate categories, and suggests that future studies with larger corpora could safely rely on animacy as a proxy for agentivity.