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		| Nikolai S. Kukushkin | 
	
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		| ''Monotone comparative statics on semilattices'' | 
	
		| ( 2021, Vol. 41 No.3 ) | 
	
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		| This paper examines to what extent monotone comparative statics analysis in the style of Milgrom and Shannon (1994) can be extended from lattices to semilattices (e.g., budget sets). A condition on preference orderings is found which is necessary and sufficient for a monotone response of the optimal choice from every subsemilattice to a perturbation of the preferences satisfying an appropriate single crossing condition. A strategic game model related to the consumption of positional goods is formulated where Nash equilibrium exists because the players' preferences satisfy our condition. | 
	
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		| Keywords: Semilattice,  Monotone comparative statics,  Single crossing,  Strategic complementarities,  Nash equilibrium | 
	
		| JEL: C7 - Game Theory and Bargaining Theory D1 - Household Behavior: General
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		| | Manuscript Received : Feb 28 2021 |  | Manuscript Accepted : Sep 17 2021 | 
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