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.
One example: Context: 'Yeah, I'm going to the desert so I'm hoping to have enough water. I'm good on food and I hunt for a lot of it anyways.' 'I've never been a good hunter. I wish I had those abilities.' 'I would part with all the food if I could get all the firewood.'
Utterance: 'That seems fair. How about water. How would that be split? I'm very concerned.'
Solution is here: Yes
Explanation: This is correct since the participant points out that the proposed deal seems fair.

Now, solve this: Context: 'I am very excited, I'm actually going camping in a week. I drink a lot of water so it's important that I bring a lot. What about you?' 'I really am! I have been watching the weather and updates about the area I will be traveling to.  They are experiencing a severe drought, so I will be in need of some extra water as well! I planned on staying an extra couple days as well.  There is a stream nearby I believe, but I'm not sure how much it has dried up.' 'That's good to hear, you always have to be careful with wild water though, it has all kind of germs. Sounds like you'll have plenty of dry firewood though. '
Utterance: 'Yes, I would be willing to let you have all the firewood for 2 of the cases of water.  How much food were you needing?'
Solution:
No