文摘
Any nonempty, compact, semi-algebraic set in class="mathmlsrc">class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0167637715001406&_mathId=si1.gif&_user=111111111&_pii=S0167637715001406&_rdoc=1&_issn=01676377&md5=7afa369d77674e3fb399ae5d85f7c291" title="Click to view the MathML source">[0,1]nclass="mathContainer hidden">class="mathCode"> is the projection of the set of mixed equilibria of a finite game with 2 actions per player on its first class="mathmlsrc">class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0167637715001406&_mathId=si2.gif&_user=111111111&_pii=S0167637715001406&_rdoc=1&_issn=01676377&md5=0c83b8d455abbfe5e616451d02988205" title="Click to view the MathML source">nclass="mathContainer hidden">class="mathCode"> coordinates. A similar result follows for sets of equilibrium payoffs. The proofs are constructive and elementary.