  Analogy completion has been a popular task in recent years for evaluating the
semantic properties of word embeddings, but the standard methodology makes a
number of assumptions about analogies that do not always hold, either in recent
benchmark datasets or when expanding into other domains. Through an analysis of
analogies in the biomedical domain, we identify three assumptions: that of a
Single Answer for any given analogy, that the pairs involved describe the Same
Relationship, and that each pair is Informative with respect to the other. We
propose modifying the standard methodology to relax these assumptions by
allowing for multiple correct answers, reporting MAP and MRR in addition to
accuracy, and using multiple example pairs. We further present BMASS, a novel
dataset for evaluating linguistic regularities in biomedical embeddings, and
demonstrate that the relationships described in the dataset pose significant
semantic challenges to current word embedding methods.
