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: '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. ' 'In that case I exchange all the water only for all your firewood' 'I can give you all the firewood - but as a diabetic, I still need at least one extra package of food for my blood sugar levels. So, as my final offer I can give you all of the firewood, and two extra packages of food. Do you agree to these terms?'
Utterance: 'No, I give out only one extra package of food'

Yes