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.

Context: 
Utterance: 'I want to make sure I'm well prepared for camping. How would you feel if I took 2 water, 1 firewood, and 2 food?'
No

Context: 'You'll definitely need some additional calories if you want to do extra hiking.  I will give you all the additional food if you give me all the additional firewood. ' 'Sounds like a deal, maybe split the water packages evenly. Can't be dehyradated while camping 🙂' 'Agreed.  Your fun trip could turn into something quite dangerous without that hydration.  '
Utterance: 'Of course, that won't be fun. ☹️ So we have agreed'
No

Context: 'I can agree to 2 food. You get 2 and I will get 1 food. That sounds fair to me. 🙂' 'Great, this is going to be a fun trip. So I get 2 water, 2 food and you get 1 water, 1 food and 3 firewood?' 'Yes, I cant wait to set off. It sounds like you have it all correct. I hope we both have a great trip. '
Utterance: 'I hope it doesn't get cold out since I won't have any firewood. You need it more than I do though, so you should have it all.'

No