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Description: Cue-based memory retrieval models have come to dominate theories of how linguistic dependencies such as subject-verb agreement are formed in comprehension. A cornerstone of the arguments in favor of such models is the grammaticality asymmetry in agreement attraction—the observation that non-subject noun phrases may interfere with the computation of agreement in ungrammatical, but not grammatical, sentences. This asymmetry is most often accounted for via the interaction of categorical number marking and the dynamics of retrieval interference. In the present paper, we challenge this interpretation of the grammaticality asymmetry, and instead argue that it is an artifact of response bias. In three forced-choice judgment experiments, we show that neutralizing response bias eliminates the grammaticality asymmetry in speeded acceptability judgments. We argue that this finding, together with the response time patterns in our experiments, favors an account that attributes attraction effects to a continuous representation of number, rather than to the dynamics of cue-based retrieval. We implement a model of grammaticality judgments, which links the continuous representation of subject number to the rate of evidence accumulation in a diffusion process. This model accounts for the presence or absence of the grammaticality asymmetry through shifts in the decisional starting point (i.e. response bias). The results have implications for the representation of number in language production and comprehension, the role of memory in the processing of linguistic dependencies, and highlight the importance of monitoring for response bias effects in judgment tasks.