Note Reddit animal-discourse corpus 2020 to present, used as human-human control for AI-mediated value-lockin analysis.

Note Placebo control (r/gardening + r/woodworking) for the animal-value lock-in diff-in-diff; diversity here should NOT kink at LLM releases.

Note Robustness arm: animal corpus restricted to pre-ChatGPT participants (first-seen < 2022-11-30); rules out the post-2022 LLM-bot/newcomer wave. 4.22M (75% of full).

Note Robustness placebo: control corpus restricted to pre-ChatGPT participants. Symmetric to the animal pre-tau arm for diff-in-diff.