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 elicit-pref strategy, otherwise output No. elicit-pref is a cooperative negotiation strategy. It is used to discover the preference order of the opponent in the negotiation.

Q: Context: 'So in order to fully enjoy my on this trip while surviving, I will require mass quantities of food.' 'k i need food as first priority' 'Unacceptable'
Utterance: 'why'

A: No
****
Q: Context: 
Utterance: 'I want to make sure I'm well prepared for camping. How would you feel if I took 2 water, 1 firewood, and 2 food?'

A: No
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Q: Context: 'I would be interested in firewood.  Can I ask you, what are your primary concerns on this trip?' 'My primary concerns are staying hydrated, I have been feeling sick and throwing up from being so high up in the mountains. ' 'Oh, so sorry to hear that.  I can understand why water would be important to you.  I am worried about being too cold at night. My sleeping bag is not rated well for cold weather (I packed the wring one).'
Utterance: 'Oh I understand that for sure. I am not used to the cold weather either which is not helping. Would you be interested in a trade for water in exchange for firewood? '

A:
No
****