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: 'That sounds like so much fun! I hope we get to hike some. I have my four month old baby with us which is exciting. I'm worried I didn't bring enough water for his bottles, though.' 'That sucks, you need to be hydrated. What supplies do you require? My family loves to grill, so we do require food.' 'Grilling is so much fun! We left our grill at home so we can't really do that. I will trade you some food for some water if you would like?'
Utterance: 'sure that sounds fair'

A: Yes
****
Q: Context: 'I need at least one firewood to cook my food. Can you give me one firewood for all the water?' 'I'm sorry. I won't be able to do that.' 'SO you will give me 3 food, no firewood and 2 water?'
Utterance: 'Because I get cold easily and need water for cleaning, my final offer is 3 food/1 water for you and 3 firewood/2 water for me. Because I'm not getting any food, anything less, I cannot do.'

A: Yes
****
Q: Context: 'I would really like to have 3 waters and 3 firewood because this is my first time camping and I don't have survival skills. ' 'You must be a comedian. We will need to come to a compromise because there's no way that's going to happen. I am like a water buffalo so I'll need at least two waters. In addition, my family is from the South and will need firewood as well.' 'I can't swim too. I think two waters will help me to survive on this trip and I will need at least two firewood to make fish or other food items for my family. '
Utterance: 'You don't need this water to swim. You can take two of the food if you're worried about food. I will take two water and two firewood since I have a large family to nourish and keep warm. Your initial suggestion of 3 waters and firewood is laughable. Please provide a realistic compromise.'

A:
Yes
****