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 don't have to eat the poison mushrooms. You can catch some fish from the river or hunt for small animals.  You have all of the firewood so cooking the food should not be a problem.' 'I won't willingly eat the poisonous mushrooms, but it could be very hard to tell the difference from safe and toxic ones.  I understand you will be staying in your area for a few extra days, but can you catch fish or hunt for small animals in your area too?' 'I do not have any extra firewood to do so.☹️  So if I can keep 1 package of firewood so I hunt and cook the fish.  I will give you 1 package of the food.'
Utterance: 'I would be willing to give up 1 package of the firewood to you for 1 package of the food.  '

A: No
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Q: Context: 'Hey, Nice getting to interact with you. I would need additional packages of food as I'm camping with Family and my kids tend to get hungry often.' 'I also have a family I am camping with several small childern and my wife who is pregnant. I need plenty of firewood and water.'
Utterance: 'I get it, in that case and to be a fair deal. I will have 2 of food, 1 of water and firewood each.'

A: Yes
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Q: Context: 'That's right. Since you would be getting food from your sister, while I am camping alone, you would be getting more food pretty soon. ' 'umm. I think the best and fair deal is a complete swap of water for food and you get 2 fire wood. ' 'Since the food can have some water and moisture in it, let's do 3 waters from me for your 3 food. How does that sound?'
Utterance: 'That sounds very fair! I love it you will love these steaks. 🙂🙂'

A:
Yes
****