This dissertation presents a series of case studies concerned with whether the signal in a given set of measurements that we take in the course of linguistic inquiry reflects grammatical competence or performance factors. We know that performance and competence do not always covary, yet it is not uncommon to assume that measurements that we take…

Reference set computation -- the construction of a (global) comparison set to determine whether a given derivation is appropriate in context -- comes with a processing cost. I argue that this cost is directly visible at the acquisition stage: In those linguistic areas in which it has been independently established that such computation is indeed…