yea-sayer

Noun

yeasayer (plural yeasayers)

1. One whose attitude is positive, optimistic, confidently affirmative.

   Synonyms:

   optimist, can-doer

2. (derogatory) One who habitually agrees uncritically.
   • The “yeasayer effect” arises in AI models trained using reinforcement learning from human feedback (RLHF)—human “data labellers” rate the answer generated by the model as being either acceptable or not.2025 June 14, Melissa Heikkilä, “AI leaders rein in ‘sycophantic’ chatbots that flatter users”, in FT Weekend (Companies & Markets section), London: The Financial Times Ltd., →ISSN, →OCLC, page 12

   Synonyms:

   yes man, doormat, kowtower

   Antonyms:

   naysayer, nay-sayer