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.

Ex Input:
Context: 'yes we have to supply more how much you want' 'I would like 3 firewood, and 2 food.  You can have 1 food and all of the water.' 'oh okay I will send you what are the materials you have'
Utterance: 'I already have a good supply of fresh water from the lake I will be camping by, and can hunt for some food but not all.  What are you in need of?'

Ex Output:
Yes


Ex Input:
Context: 'HI, I will have all of the packages of food and 2 waters and 2 firewood and you can have the rest. Unless none is needed for you then I will take them all.' 'i will need 3 firewood packets.  I have a terrible disease that prevents my circulation from working properly.' 'That does sound bad. I am going camping and my kids might want to stay up late so I will need extra firewood for this to keep light and more warmth. I will take all 3 extra of the food and the water but I need 2 firewood also.'
Utterance: 'no that won't work.  I will give you 3 food and 1 water.  I will take 3 wood and 2 waters.'

Ex Output:
No


Ex Input:
Context: 'Mine is firewood with second being food.' 'I'm definitely willing to give up some food for some firewood: That seems like a place where we can come to an arrangement: Would you like to make an opening offer? ' 'Sure!  I figure I can go with little water as we can get it from the stream and boil it.  So for water I would be willing to give you 2 packages.  Would that be fair?'
Utterance: 'so If I understand correctly, the Deal is I get 3 Food and 2 Water: While you get 3 Firewood and 1 Water?'

Ex Output:

No