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: 'Yes, that's very true. I would be willing to give up water for more firewood.' 'I like that. I could help you out. I'd be interested in giving you some extra food for extra water. We like to go far from campsite to hike and get up to high elevation, so i need to pack extra water just in case. We go during day, when it's warmest and need extra food in case we come back at nigh time or get lost! Not ideal. ' 'You can never be too prepared. We stay closer to camp as we have little ones with us on this trip.'
Utterance: 'are you interested in taking 1 firewood, all 3 foods and 1 water ? And then what's left would be to us ? '

No