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: 'I would also like a little extra food for my kids. Maybe we can split it somehow?' 'Ok, I am willing to give you one food, in exchange for two firewoods, that would mean you get 3 waters, 1 food and 1 firewood. you get 5 items, while i get 4.' 'If I only get 1 food, than I would like 2 firewood. So you get 2 food, 1 firewood, and 1 water.'
Utterance: 'No i do not need water, as i am camping near a potable stream. I would like 2 firewood. It is only fair that i get two firewood, since you are getting more supplies (5), i think i should be able to choose what 4 i should get.'

A: Yes
****
Q: Context: 'I am! It is the perfect way to get away and still manage to social distance! I am worried about having enough water though, are you short on any supplies?' 'I think I'm good. I'm not 100% sure. My husband likes to do adventures on the fly. He got these water filter straw thingies from Amazon and said that if we run out of the water I packed, that we can drink the water in the lake but I don't really trust the straws.' 'Sounds like you need water too. How about you take 2 water, 1 food, and 1 firewood?'
Utterance: 'I don't know, you said you're worried about having enough water too. I'm excited to make campfires though! My kid hasn't had a campfire smore yet so I'm super excited to see his face of joy when he experiences it.'

A: No
****
Q: Context: 'Hello there I was just thinking of the upcoming camping trip.' 'I'm sorry about that, accidentally hit that send button lol! I was thinking about it as well. I'm pretty excited. How about you?' 'I was just thinking about the logistics and how to prioritize the various items.'
Utterance: 'Same here. I'll go ahead and list some of what I need and you let me know if you will need the same as well. I need some extra water for our camping trip as well as some additional food. '

A:
No
****