The Entropy Reduction Hypothesis (Hale, 2006) derives the subject-object asymmetry in Korean relative clauses. This asymmetry has been observed by Kwon, Polinsky, and Kluender (2006), among others. Agreement between the Entropy Reduction predictions and the available empirical data suggests that the heightened comprehension difficulty attested in object-extracted relatives is due to distinctive incremental parser states associated with comparatively greater temporary ambiguity.