Scalar implicature rates vary within and across adjectival scales

Recent experimental literature has investigated across-scale variation in scalar implicature calculation, probing why lexical scales differ from each other in their likelihood of being strengthened (e.g. old $\rightarrow $ not ancient v. smart $\rightarrow $ not brilliant). But in existing studies of this scalar diversity, less attention has been paid to potential variation introduced by the carrier sentences that scales occur in. In this paper, we carry out a systematic investigation of the role of sentential context on scalar diversity, focusing on scales formed by two gradable adjectives. We find within-scale variation: different subject nouns (e.g. The employee is smart v. The scientist is smart) have a significant effect on how robustly a scalar implicature arises. We then explore the relationship between a noun's prior likelihood of exhibiting the stronger adjectival property (e.g. brilliance) and the rate of implicature calculation, and find that they are negatively correlated. We also test whether a previously identified factor in scalar diversity, adjectival threshold distance between the weaker (smart) and stronger (brilliant) adjective, is sensitive to the subject noun manipulation, but do not find evidence for this. In addition to their theoretical import, our findings also highlight the methodological importance of controlling carrier sentences.