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 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.'

Ex Output:
Yes


Ex Input:
Context: 'Hi, what is your highest priority item?' 'I would love to have extra food for my trip, bringing the family! how about you?' 'I agree, it will be tricky to find extra food while camping. I'm sure we can figure out something that works for both of us... the water is also very important to me because it's supposed to be hot. There is plenty of wood where I'm going, so you can have the firewood. Would you be willing to take 3 firewood, 1 food and 1 food?'
Utterance: 'I would like at least 2 food, how does me getting 2 food, 1 water,2 firewood sound?'

Ex Output:
No


Ex Input:
Context: 'Yes, that sounds good to me!' 'How about water? do you need? I can offer 2 of these for 1 pack of food' 'I have plenty of water right now, but need at least 1 pack of food for myself.'
Utterance: 'OK. Do I get the water then? You can at least take a pack'

Ex Output:

No