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.

Q: Context: 'You take 2 waters, I'll take 2 firewood and 2 food?' 'What about you take 1 water and the firewood.  I take 2 waters and all the food' 'That leaves me with very little. Can I have 1 water, 2 firewood, and 2 food?'
Utterance: 'you would get 1 water and all 3 firewood.  I would get 2 water and all 3 food.  You have one less than me but the food is worth less'

A: Yes
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Q: Context: 'So, it looks like we have reached a compromise. ' 'Yes we have. Just to clarify, I will get two packages of water and you will get one. I will also get two packages of firewood and you will get 1. And then I will get 1 package of firewood and you will get 2,' 'I will get two packages of food and you will receive one. I will get one jug of water and you will receive two. I will get one bundle of firewood and you will receive two.'
Utterance: 'Perfect. It has been a pleasure negotiating!'

A: No
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Q: Context: 'I would like 2 food, but you may have one. I wouldn't want you to be too hungry!' 'I don't want to be too hungry either but I think perhaps I might need an extra water to compensate for the lack of food.' 'Since I am giving you all of the firewood that you said was most important to you, I feel I should get at least the same amount of items as you, especially since you are getting exactly the firewood you want. I will need to stick to three waters and two food.'
Utterance: 'The firewood is most important to me to be sure. However, if you get more food and all of the water I could end up going hungry.☹️'

A:
Yes
****