Definition: The input is taken from a negotiation between two participants who take the role of campsite neighbors and negotiate for Food, Water, and Firewood packages, based on their individual preferences and requirements. Given an utterance and recent dialogue context containing past 3 utterances (wherever available), output Yes if the utterance contains the vouch-fair strategy, otherwise output No. vouch-fair is a selfish negotiation strategy. It is used to call out fairness for personal benefit, either when acknowledging a fair deal or when the opponent offers a deal that benefits them. This can be through an explicit call out or can be implied.
Input: Context: 'I can't give out all the water. I need to be hydrated as well. ' 'You already have all the basics, though, so you won't lack sufficient water to be hydrated. I have a serious medical condition that requires that I have access to additional water. ' 'The maximum bundle I can give is all packages of food + 1 package of water'
Utterance: 'Sorry, that won't work for me. I've already said that I have a medical condition that requires additional water. You do not need that much water just to be hydrated -- you already have basic water. I can give you all of the firewood, but I need all of the water. '

Yes