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.

Example Input: Context: 'I'm good! I'm looking forward to my camping trip this weekend. How about you?' 'I'm good as well, I hope the weather works with me 🙂' 'Sending good luck your way! Any items in particular you need for your trip?'
Utterance: 'Well, I'll start with a trial offer and we'll go from there'
Example Output: No

Example Input: Context: 'I could also use the extra food, so can we resolve it amicably?  Coin flip maybe?' 'That's a good idea.  I'll trust you to do the coin flip.  ' 'Sure.  🙂  I'll grab a coin.'
Utterance: 'Calling tails.  '
Example Output: No

Example Input: Context: 'Initially you were willing to take the 2 packages of firewood. If you have all three I won't be able to cook any of this fish and it will all go to waste. ☹️' 'Didn't you bring any firewood at all with you?' 'Yes, but the firewood I have will be used to keep us warm tonight.  Like you mentioned before it will be a bit chilly tonight.'
Utterance: 'Ahh, I forgot about that. OK. I'll take 2 packages of firewood, give you 2 waters, and 1 food packages as you do have some fish to cook and I don't. Do we have a deal?'
Example Output:
Yes