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.

Ex Input:
Context: 'I also need water.  You would not believe how much my family and I sweat!' 'I understand. I am unfortunately sick and need the warmth of the fire and water to take my medication or I will die very soon' 'You can have all of the firewood, we just need 1 water '
Utterance: 'That is fair. Could I also have 1 food so I do not starve'

Ex Output:
Yes


Ex Input:
Context: 'Awesome - same, I also need a ton of food. Will firewood be of interest to you as well? I'll be happy to compensate in this way' 'Firewood is not overly interesting to me, but water is somewhat enticing.' 'Ok, great - I can give you all of my waters in exchange for a majority of the food and half of firewood'
Utterance: 'Half of firewood? There are 3 so one of us has to get more. I would need more of that. '

Ex Output:
No


Ex Input:
Context: 
Utterance: 'Hi! I'm exited to negotiate a deal with you today. How are you doing?'

Ex Output:

No