Frustratingly easy meta-embedding-computing meta-embeddings by averaging source word embeddings

Abstract

Creating accurate meta-embeddings from pretrained source embeddings has received attention lately. Methods based on global and locally-linear transformation and concatenation have shown to produce accurate metaembeddings. In this paper, we show that the arithmetic mean of two distinct word embedding sets yields a performant meta-embedding that is comparable or better than more complex meta-embedding learning methods. The result seems counter-intuitive given that vector spaces in different source embeddings are not comparable and cannot be simply averaged. We give insight into why averaging can still produce accurate meta-embedding despite the incomparability of the source vector spaces.