Good question.
I can’t tell, if saying that you will reject unfair splits would be a threat by the definition in my above comment. For it to be a threat, you would have to only do it if the other person cares about the thing being split. But in the Ultimatum Game both players per definition care about it, so I have a hard time thinking about what you would do if someone offers you a unfair split of something they don’t care about (how can a split even be unfair, if only one person values the thing being split?).
Thanks! Looks like the “don’t think” condition is very close to the “no instruction” baseline in your results as well. If I understand the bottom figure correctly, the model can even somewhat control where during a longer task the concept is represented the strongest?
Happy to chat, I’ll send you a DM.