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Kakutani fixed-point theorem

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4480: 957: 689: 783:, shown on the figure at the right, satisfies all Kakutani's conditions, and indeed it has many fixed points: any point on the 45° line (dotted line in red) which intersects the graph of the function (shaded in grey) is a fixed point, so in fact there is an infinity of fixed points in this particular case. For example, 3221:-simplex is the higher-dimensional version of a triangle. Proving Kakutani's theorem for set-valued function defined on a simplex is not essentially different from proving it for intervals. The additional complexity in the higher-dimensional case exists in the first step of chopping up the domain into finer subpieces: 2315:
Thus, the closed intervals form a sequence of subintervals of . Condition (2) tells us that these subintervals continue to become smaller while condition (3)–(6) tell us that the function φ shifts the left end of each subinterval to its right and shifts the right end of each subinterval to its left.
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does not equate supply and demand everywhere. The challenge here is to construct φ so that it has this property while at the same time satisfying the conditions in Kakutani's theorem. If this can be done then φ has a fixed point according to the theorem. Given the way it was constructed, this fixed
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Otherwise, we can write the following. Recall that we can parameterize a line between two points a and b by (1-t)a + tb. Using our finding above that q<x<p, we can create such a line between p and q as a function of x (notice the fractions below are on the unit interval). By a convenient
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recalls that Kakutani once asked him at a conference why so many economists had attended his talk. When Binmore told him that it was probably because of the Kakutani fixed point theorem, Kakutani was puzzled and replied, "What is the Kakutani fixed point theorem?"
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theory in economics, Kakutani's theorem has been used to prove the existence of set of prices which simultaneously equate supply with demand in all markets of an economy. The existence of such prices had been an open question in economics going back to at least
3170: 935: 3259:. Once again we employ the same technique of creating increasingly finer subdivisions. But instead of triangles with straight edges as in the case of n-simplices, we now use triangles with curved edges. In formal terms, we find a simplex which covers 1258: 1557:) is nonempty since there is always at least one best response. It is convex, since a mixture of two best-responses for a player is still a best-response for the player. It can be proved that φ has a closed graph. 1564:
of the game is defined as a fixed point of φ, i.e. a tuple of strategies where each player's strategy is a best response to the strategies of the other players. Kakutani's theorem ensures that this fixed point
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theory. Chapter 5 uses Kakutani's theorem to prove the existence of equilibrium prices. Appendix C includes a proof of Kakutani's theorem and discusses its relationship with other mathematical results used in
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Once these changes have been made to the first step, the second and third steps of finding a limiting point and proving that it is a fixed point are almost unchanged from the one-dimensional case.
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While in the one-dimensional case we could use elementary arguments to pick one of the half-intervals in a way that its end-points were moved in opposite directions, in the case of simplices the
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Brouwer's fixed-point theorem is a special case of Kakutani fixed-point theorem. Conversely, Kakutani fixed-point theorem is an immediate generalization via the
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The function has no fixed point. Though it satisfies all other requirements of Kakutani's theorem, its graph is not closed; for example, consider the sequences
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is required to be closed-valued in the alternative statement of the Kakutani theorem, the Closed Graph Theorem implies that the two statements are equivalent.
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of the real line. Moreover, the proof of this case is instructive since its general strategy can be carried over to the higher-dimensional case as well.
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The function has no fixed point. Though it satisfies all other requirements of Kakutani's theorem, its value fails to be convex at
4404: 1708: 4049: 2010: 3751: 79: 1545:) associates with each tuple a new tuple where each player's strategy is her best response to other players' strategies in 1128:{\displaystyle \varphi (x)={\begin{cases}3/4&0\leq x<0.5\\\{3/4,1/4\}&x=0.5\\1/4&0.5<x\leq 1\end{cases}}} 4514: 4504: 4200: 4003: 3455:
on S which has a closed graph and the property that φ(x) is non-empty and convex for all x ∈ S. Then the set of
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This statement of Kakutani's theorem is completely equivalent to the statement given at the beginning of this article.
3998: 2780: 2685: 71: 4465: 4225: 3165:{\displaystyle x=\left({\frac {x-q^{*}}{p^{*}-q^{*}}}\right)p^{*}+\left(1-{\frac {x-q^{*}}{p^{*}-q^{*}}}\right)q^{*}} 4419: 4343: 426: 378: 4460: 2684:
We have a pair of sequences of intervals, and we would like to show them to converge to a limiting point with the
930:{\displaystyle \varphi (x)={\begin{cases}3/4&0\leq x<0.5\\{}&x=0.5\\1/4&0.5<x\leq 1\end{cases}}} 82:
defined on compact, convex subsets of Euclidean spaces. Kakutani's theorem extends this to set-valued functions.
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McKenzie, Lionel (1954). "On Equilibrium in Graham's Model of World Trade and Other Competitive Systems".
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in every finite game with mixed strategies for any finite number of players. This work later earned him a
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is the cartesian product of all these simplices. It is indeed a nonempty, compact and convex subset of
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Kakutani's theorem for n-simplices can be used to prove the theorem for an arbitrary compact, convex
1394: 1253:{\displaystyle \varphi (x)={\begin{cases}3/4&0\leq x<0.5\\1/4&0.5\leq x\leq 1\end{cases}}} 47: 3752:"A Further Generalization of the Kakutani Fixed Point Theorem, with Application to Nash Equilibrium" 1180: 1009: 825: 4389: 4327: 4041: 3977: 3452: 3268: 2773: 2093: 1644: 1581: 1575: 1344: 609: 163: 43: 39: 3932:(Standard reference on fixed-point theory for economists. Includes a proof of Kakutani's theorem.) 1669: 1635:
Kakutani's fixed-point theorem is used in proving the existence of cake allocations that are both
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There is another version that the statement of the theorem becomes the same as that in the
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be any point in φ(1). Then, conditions (1)–(4) are immediately fulfilled. Moreover, since
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on the closed interval which satisfies the conditions of Kakutani's fixed-point theorem.
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Create a sequence of subdivisions of with adjacent points moving in opposite directions.
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to a set containing it. The Kakutani fixed point theorem is a generalization of the
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point must correspond to a price-tuple which equates supply with demand everywhere.
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are the simplest objects on which Kakutani's theorem can be proved. Informally, a
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The proof of Kakutani's theorem is simplest for set-valued functions defined over
3861: 3654: 787: = 0.72 (dashed line in blue) is a fixed point since 0.72 ∈ . 4374: 4364: 4271: 4073: 3470: 3434: 3391: 2776: 2729: 1513:-tuple of probabilities summing up to 1, so each player's strategy space is the 1478: 1457: 1309: 129: 98: 55: 4307: 4147: 4143: 4139: 3922: 3795:"Fixed-point and Minimax Theorems in Locally Convex Topological Linear Spaces" 3650: 3438: 3395: 3002: 2441: 1313: 360: 133: 51: 3736: 3225:
Where we split intervals into two at the middle in the one-dimensional case,
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By the approximate selection theorem, there exists a sequence of continuous
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Some sources, including Kakutani's original paper, use the concept of
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satisfies all Kakutani's conditions, and indeed it has a fixed point:
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Kakutani's fixed-point theorem was extended to infinite-dimensional
3271:. Then we can apply the already established result for n-simplices. 1413:→2 has a closed graph if and only if it is upper hemicontinuous and 688: 3927:
Fixed Point Theorems with Applications to Economics and Game Theory
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Fixed Point Theorems with Applications to Economics and Game Theory
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used the Kakutani fixed point theorem to prove a major result in
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is used to guarantee the existence of an appropriate subsimplex.
4014: 3408:. Let φ: S→2 be a Kakutani map. Then φ has a fixed point. 3496:(1941). "A generalization of Brouwer's fixed point theorem". 74:. The Brouwer fixed point theorem is a fundamental result in 3635:
Aliprantis, Charlambos; Kim C. Border (1999). "Chapter 17".
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The corresponding result for single-valued functions is the
2799:*). Since the graph of φ is closed it must be the case that 1481:. Stated informally, the theorem implies the existence of a 3381:
Then the Kakutani–Glicksberg–Fan theorem can be stated as:
1776:{\displaystyle \operatorname {graph} (f_{n})\subset _{1/n}} 1246: 1121: 923: 1783:. By Brouwer fixed-point theorem, there exists a sequence 1462:
The Kakutani fixed point theorem can be used to prove the
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is used to break up a simplex into smaller sub-simplices.
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for set-valued functions, which says that for a compact
3898:(1st ed.). Oxford University Press. p. 256. 97:. It has subsequently found widespread application in 3721:. Springer International Publishing. pp. 68–70. 3014: 2013: 1980: 1960: 1872: 1816: 1789: 1711: 1672: 1159: 988: 804: 711: 612: 592: 543: 510: 477: 429: 381: 301: 3860:; Andrzej Granas (2003). "Chapter II, Section 5.8". 1589:. The first proof of this result was constructed by 1505:
chosen by each player in a game. If each player has
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Infinite Dimensional Analysis: A Hitchhiker's Guide
2319:Such a sequence can be constructed as follows. Let 1509:possible actions, then each player's strategy is a 4370:Spectral theory of ordinary differential equations 3956: 3164: 2049: 1999: 1966: 1943: 1858: 1802: 1775: 1697: 1252: 1127: 929: 775: 633: 598: 578: 529: 496: 463: 415: 313: 1974:is compact, we can take a convergent subsequence 3756:Proceedings of the American Mathematical Society 78:which proves the existence of fixed points for 2956:Show that the limiting point is a fixed point. 651: → 2 be a set-valued function. Then 263:. Formally it can be seen just as an ordinary 4026: 1150:Consider the following function defined on : 1146:A function that does not satisfy closed graph 979:Consider the following function defined on : 464:{\displaystyle \{y_{n}\}_{n\in \mathbb {N} }} 416:{\displaystyle \{x_{n}\}_{n\in \mathbb {N} }} 8: 3630: 3628: 1072: 1044: 701:A function with infinitely many fixed points 444: 430: 396: 382: 27:Fixed-point theorem for set-valued functions 3852: 3850: 3848: 3369:) is non-empty, compact and convex for all 4061: 4033: 4019: 4011: 3488: 3486: 2679:Find a limiting point of the subdivisions. 952:A function that does not satisfy convexity 3828: 3818: 3564: 3554: 3156: 3138: 3125: 3113: 3100: 3080: 3063: 3050: 3038: 3025: 3013: 2012: 1985: 1979: 1959: 1931: 1927: 1893: 1880: 1871: 1850: 1834: 1821: 1815: 1794: 1788: 1763: 1759: 1725: 1710: 1677: 1671: 1651:Relation to Brouwer's fixed-point theorem 1218: 1186: 1175: 1158: 1093: 1064: 1050: 1015: 1004: 987: 895: 860: 831: 820: 803: 762: 739: 710: 611: 591: 567: 548: 542: 515: 509: 482: 476: 455: 454: 447: 437: 428: 407: 406: 399: 389: 380: 300: 4323:Group algebra of a locally compact group 3281:locally convex topological vector spaces 2772:) lies in a compact set, it must have a 2154: 1364:is non-empty, closed, and convex for all 955: 687: 3896:Playing for Real: A Text on Game Theory 3482: 3406:locally convex topological vector space 1944:{\displaystyle (x_{n},x_{n})\in _{1/n}} 50:for a set-valued function defined on a 3531:"Equilibrium Points in N-Person Games" 3521: 3519: 976:is essential for the theorem to hold. 579:{\displaystyle y_{n}\in \phi (x_{n})} 7: 3365:if it is upper hemicontinuous and φ( 3275:Infinite-dimensional generalizations 2354:∈ φ(0) ⊂ , it must be the case that 791:A function with a unique fixed point 1650: 1859:{\displaystyle f_{n}(x_{n})=x_{n}} 25: 335: → 2 is said to have a 251:is some rule that associates one 4479: 4478: 4405:Topological quantum field theory 3892:"When Do Nash Equilibria Exist?" 3357:→2 be a set-valued function. If 2926:Then we have the situation that 2815:*). Moreover, by condition (5), 2542:) is non-empty, there must be a 3263:and then move the problem from 2150:with the following properties: 960:A function without fixed points 948:is contained in the interval . 197:is non-empty and convex for all 3659:. Cambridge University Press. 3592:. Cambridge University Press. 3459:of φ is non-empty and compact. 3361:is convex, then φ is termed a 3298:A set-valued function φ:  2044: 2038: 2026: 2014: 1991: 1924: 1920: 1914: 1905: 1899: 1873: 1840: 1827: 1756: 1752: 1746: 1737: 1731: 1718: 1689: 1393:We can show this by using the 1169: 1163: 998: 992: 944:= 0.5 is a fixed point, since 874: 862: 814: 808: 770: 727: 721: 715: 628: 622: 573: 560: 521: 488: 331:A set-valued function φ:  172:with the following properties: 1: 4201:Uniform boundedness principle 3929:. Cambridge University Press. 3510:10.1215/S0012-7094-41-00838-4 3469:In his game theory textbook, 3415:Tychonoff fixed-point theorem 1657:approximate selection theorem 634:{\displaystyle y\in \phi (x)} 85:The theorem was developed by 3959:General Competitive Analysis 3535:Proc. Natl. Acad. Sci. U.S.A 2674:satisfy conditions (1)–(6). 1698:{\displaystyle f_{n}:S\to S} 776:{\displaystyle \varphi (x)=} 36:Kakutani fixed-point theorem 18:Kakutani fixed point theorem 4510:Theorems in convex geometry 3999:Encyclopedia of Mathematics 3210:In dimensions greater one, 3175:it once again follows that 2686:Bolzano-Weierstrass theorem 2371:Now suppose we have chosen 1293:while stating the theorem: 113:Kakutani's theorem states: 72:Brouwer fixed point theorem 4536: 4520:General equilibrium theory 4344:Invariant subspace problem 3656:General Equilibrium Theory 3267:to the simplex by using a 2997:writing of x, and since φ( 2057:since it is a closed set. 2000:{\displaystyle x_{n}\to x} 1643:. This result is known as 1628: 1573: 1455: 1444: 1421:) is a closed set for all 530:{\displaystyle y_{n}\to y} 497:{\displaystyle x_{n}\to x} 287: → 2, such that 4474: 4064: 3940:; Andrzej Granas (2003). 3750:Glicksberg, I.L. (1952). 3717:Shapiro, Joel H. (2016). 3639:(3rd ed.). Springer. 3498:Duke Mathematical Journal 3351:topological vector spaces 2407:satisfying (1)–(6). Let, 2340:be any point in φ(0) and 2186: 2162: 295:) is non-empty for every 89:in 1941, and was used by 4313:Spectrum of a C*-algebra 3799:Proc Natl Acad Sci U S A 2852:) ≤ 2 by condition (2), 2823:* and by condition (6), 2634:It can be verified that 1487:Nobel Prize in Economics 1405:, a set-valued function 321:. Some prefer the term 66:, i.e. a point which is 4410:Noncommutative geometry 3976:(Standard reference on 3619:A Course in Game Theory 3588:Border, Kim C. (1989). 3451:. Let φ: S→2 be a 3227:barycentric subdivision 3195:is a fixed point of φ. 2993:is a fixed point of φ. 375:i.e. for all sequences 4466:Tomita–Takesaki theory 4441:Approximation property 4385:Calculus of variations 3782:on September 22, 2017. 3166: 2736:. Since our sequence ( 2051: 2001: 1968: 1945: 1860: 1804: 1777: 1699: 1447:Mathematical economics 1353:with the property that 1254: 1129: 961: 931: 777: 697: 635: 600: 580: 531: 498: 465: 417: 315: 314:{\displaystyle x\in X} 93:in his description of 4461:Banach–Mazur distance 4424:Generalized functions 3955:; F. H. Hahn (1971). 3890:Binmore, Ken (2007). 3820:10.1073/pnas.38.2.121 3719:A Fixed-Point Farrago 3621:. Cambridge, MA: MIT. 3167: 2052: 2002: 1969: 1946: 1861: 1805: 1803:{\displaystyle x_{n}} 1778: 1700: 1429:are Hausdorff (being 1285:Alternative statement 1255: 1130: 964:The requirement that 959: 932: 778: 691: 636: 601: 581: 532: 499: 466: 418: 316: 48:sufficient conditions 32:mathematical analysis 4515:Theorems in topology 4505:Fixed-point theorems 4206:Kakutani fixed-point 4191:Riesz representation 3613:Osborne, Martin J.; 3556:10.1073/pnas.36.1.48 3305:upper hemicontinuous 3295:Upper hemicontinuity 3012: 2724:). This lies in the 2558:. In this case let, 2011: 1978: 1958: 1870: 1814: 1787: 1709: 1670: 1608:of commodity prices. 1395:closed graph theorem 1342:upper hemicontinuous 1291:upper hemicontinuity 1157: 986: 972:) be convex for all 802: 709: 610: 590: 541: 508: 475: 427: 379: 299: 80:continuous functions 44:set-valued functions 4390:Functional calculus 4349:Mahler's conjecture 4328:Von Neumann algebra 4042:Functional analysis 3978:general equilibrium 3811:1952PNAS...38..121F 3547:1950PNAS...36...48N 3453:set-valued function 3269:deformation retract 2781:Bolzano-Weierstrass 2734:Tychonoff's theorem 2538:Otherwise, since φ( 2094:set-valued function 1582:general equilibrium 1576:General equilibrium 1570:General equilibrium 1345:set-valued function 259:with each point in 238:set-valued function 233:Set-valued function 164:set-valued function 40:fixed-point theorem 4415:Riemann hypothesis 4114:Topological vector 3994:"Kakutani theorem" 3942:Fixed Point Theory 3863:Fixed Point Theory 3162: 2047: 1997: 1964: 1941: 1856: 1800: 1773: 1695: 1664: 1250: 1245: 1125: 1120: 962: 927: 922: 773: 698: 631: 596: 576: 527: 494: 461: 413: 311: 4492: 4491: 4395:Integral operator 4172: 4171: 3982: 3970:978-0-8162-0275-1 3953:Arrow, Kenneth J. 3948: 3933: 3905:978-0-19-804114-6 3876:978-0-387-00173-9 3867:(limited preview) 3728:978-3-319-27978-7 3666:978-0-521-56473-1 3615:Rubinstein, Ariel 3285:Irving Glicksberg 3179:must belong to φ( 3145: 3070: 2726:cartesian product 2311: 2310: 1967:{\displaystyle S} 1662: 1631:Fair cake-cutting 1466:in the theory of 752: 692:Fixed points for 599:{\displaystyle n} 16:(Redirected from 4527: 4482: 4481: 4400:Jones polynomial 4318:Operator algebra 4062: 4035: 4028: 4021: 4012: 4007: 3975: 3974: 3962: 3946: 3945: 3931: 3930: 3910: 3909: 3887: 3881: 3880: 3868: 3854: 3843: 3842: 3832: 3822: 3793:Fan, Ky (1952). 3790: 3784: 3783: 3778:. Archived from 3747: 3741: 3740: 3714: 3708: 3707: 3677: 3671: 3670: 3647: 3641: 3640: 3632: 3623: 3622: 3610: 3604: 3603: 3585: 3579: 3578: 3568: 3558: 3523: 3514: 3513: 3494:Kakutani, Shizuo 3490: 3236:result known as 3171: 3169: 3168: 3163: 3161: 3160: 3151: 3147: 3146: 3144: 3143: 3142: 3130: 3129: 3119: 3118: 3117: 3101: 3085: 3084: 3075: 3071: 3069: 3068: 3067: 3055: 3054: 3044: 3043: 3042: 3026: 2728:×××, which is a 2463:, then we take, 2155: 2087:closed intervals 2082: 2081: 2077: 2056: 2054: 2053: 2048: 2006: 2004: 2003: 1998: 1990: 1989: 1973: 1971: 1970: 1965: 1950: 1948: 1947: 1942: 1940: 1939: 1935: 1898: 1897: 1885: 1884: 1865: 1863: 1862: 1857: 1855: 1854: 1839: 1838: 1826: 1825: 1809: 1807: 1806: 1801: 1799: 1798: 1782: 1780: 1779: 1774: 1772: 1771: 1767: 1730: 1729: 1704: 1702: 1701: 1696: 1682: 1681: 1645:Weller's theorem 1641:Pareto efficient 1562:Nash equilibrium 1515:standard simplex 1503:mixed strategies 1489:. In this case: 1483:Nash equilibrium 1427:Euclidean spaces 1259: 1257: 1256: 1251: 1249: 1248: 1222: 1190: 1134: 1132: 1131: 1126: 1124: 1123: 1097: 1068: 1054: 1019: 936: 934: 933: 928: 926: 925: 899: 861: 835: 782: 780: 779: 774: 766: 750: 743: 640: 638: 637: 632: 605: 603: 602: 597: 585: 583: 582: 577: 572: 571: 553: 552: 536: 534: 533: 528: 520: 519: 503: 501: 500: 495: 487: 486: 470: 468: 467: 462: 460: 459: 458: 442: 441: 422: 420: 419: 414: 412: 411: 410: 394: 393: 373:product topology 320: 318: 317: 312: 21: 4535: 4534: 4530: 4529: 4528: 4526: 4525: 4524: 4495: 4494: 4493: 4488: 4470: 4434:Advanced topics 4429: 4353: 4332: 4291: 4257:Hilbert–Schmidt 4230: 4221:Gelfand–Naimark 4168: 4118: 4053: 4039: 3992: 3989: 3971: 3951: 3938:Dugundji, James 3936: 3921: 3918: 3916:Further reading 3913: 3906: 3889: 3888: 3884: 3877: 3866: 3858:Dugundji, James 3856: 3855: 3846: 3792: 3791: 3787: 3768:10.2307/2032478 3749: 3748: 3744: 3729: 3716: 3715: 3711: 3696:10.2307/1907539 3679: 3678: 3674: 3667: 3649: 3648: 3644: 3634: 3633: 3626: 3612: 3611: 3607: 3600: 3587: 3586: 3582: 3525: 3524: 3517: 3492: 3491: 3484: 3480: 3467: 3449:Hausdorff space 3277: 3253: 3238:Sperner's lemma 3208: 3191:* do and hence 3152: 3134: 3121: 3120: 3109: 3102: 3093: 3089: 3076: 3059: 3046: 3045: 3034: 3027: 3021: 3010: 3009: 2898: 2889: 2880: 2871: 2851: 2842: 2771: 2762: 2753: 2744: 2723: 2714: 2705: 2696: 2673: 2663: 2653: 2643: 2625: 2614: 2605: 2590: 2579: 2570: 2534: 2525: 2510: 2499: 2490: 2475: 2440:∈ because is 2431: 2422: 2406: 2397: 2388: 2379: 2367: 2360: 2353: 2346: 2339: 2332: 2325: 2307: 2298: 2283: 2274: 2256: 2247: 2231: 2222: 2204: 2195: 2178: 2169: 2146:= 0, 1, … be a 2141: 2132: 2123: 2114: 2092:Let φ: →2 be a 2083: 2079: 2075: 2073: 2072: 2064: 2059: 2009: 2008: 1981: 1976: 1975: 1956: 1955: 1923: 1889: 1876: 1868: 1867: 1846: 1830: 1817: 1812: 1811: 1790: 1785: 1784: 1755: 1721: 1707: 1706: 1673: 1668: 1667: 1653: 1633: 1627: 1611:The function φ( 1591:Lionel McKenzie 1578: 1572: 1541:The function φ( 1464:minimax theorem 1460: 1454: 1449: 1443: 1321:Euclidean space 1287: 1279: 1268: 1244: 1243: 1226: 1212: 1211: 1194: 1176: 1155: 1154: 1148: 1119: 1118: 1101: 1087: 1086: 1075: 1041: 1040: 1023: 1005: 984: 983: 954: 921: 920: 903: 889: 888: 877: 857: 856: 839: 821: 800: 799: 793: 707: 706: 703: 686: 608: 607: 588: 587: 563: 544: 539: 538: 511: 506: 505: 478: 473: 472: 443: 433: 425: 424: 395: 385: 377: 376: 297: 296: 230: 160: → 2 141:Euclidean space 111: 95:Nash equilibria 87:Shizuo Kakutani 60:Euclidean space 28: 23: 22: 15: 12: 11: 5: 4533: 4531: 4523: 4522: 4517: 4512: 4507: 4497: 4496: 4490: 4489: 4487: 4486: 4475: 4472: 4471: 4469: 4468: 4463: 4458: 4453: 4451:Choquet theory 4448: 4443: 4437: 4435: 4431: 4430: 4428: 4427: 4417: 4412: 4407: 4402: 4397: 4392: 4387: 4382: 4377: 4372: 4367: 4361: 4359: 4355: 4354: 4352: 4351: 4346: 4340: 4338: 4334: 4333: 4331: 4330: 4325: 4320: 4315: 4310: 4305: 4303:Banach algebra 4299: 4297: 4293: 4292: 4290: 4289: 4284: 4279: 4274: 4269: 4264: 4259: 4254: 4249: 4244: 4238: 4236: 4232: 4231: 4229: 4228: 4226:Banach–Alaoglu 4223: 4218: 4213: 4208: 4203: 4198: 4193: 4188: 4182: 4180: 4174: 4173: 4170: 4169: 4167: 4166: 4161: 4156: 4154:Locally convex 4151: 4137: 4132: 4126: 4124: 4120: 4119: 4117: 4116: 4111: 4106: 4101: 4096: 4091: 4086: 4081: 4076: 4071: 4065: 4059: 4055: 4054: 4040: 4038: 4037: 4030: 4023: 4015: 4009: 4008: 3988: 3987:External links 3985: 3984: 3983: 3969: 3963:. Holden-Day. 3949: 3934: 3923:Border, Kim C. 3917: 3914: 3912: 3911: 3904: 3882: 3875: 3844: 3805:(2): 121–126. 3785: 3762:(1): 170–174. 3742: 3727: 3709: 3690:(2): 147–161. 3672: 3665: 3651:Starr, Ross M. 3642: 3624: 3605: 3598: 3580: 3527:Nash, J.F. Jr. 3515: 3504:(3): 457–459. 3481: 3479: 3476: 3466: 3463: 3462: 3461: 3446:locally convex 3411: 3410: 3379: 3378: 3339: 3336: 3327:) ⊂  3296: 3276: 3273: 3252: 3246: 3242: 3241: 3230: 3207: 3197: 3173: 3172: 3159: 3155: 3150: 3141: 3137: 3133: 3128: 3124: 3116: 3112: 3108: 3105: 3099: 3096: 3092: 3088: 3083: 3079: 3074: 3066: 3062: 3058: 3053: 3049: 3041: 3037: 3033: 3030: 3024: 3020: 3017: 2959: 2958: 2952: 2951: 2901: 2900: 2894: 2885: 2876: 2867: 2847: 2838: 2767: 2758: 2749: 2740: 2719: 2710: 2701: 2692: 2682: 2681: 2668: 2658: 2648: 2638: 2632: 2631: 2620: 2615: 2610: 2600: 2595: 2585: 2580: 2575: 2565: 2536: 2535: 2530: 2520: 2515: 2505: 2500: 2495: 2485: 2480: 2470: 2447:If there is a 2434: 2433: 2427: 2418: 2402: 2393: 2384: 2375: 2365: 2358: 2351: 2344: 2337: 2330: 2323: 2313: 2312: 2309: 2308: 2303: 2294: 2289: 2284: 2279: 2270: 2265: 2259: 2258: 2252: 2243: 2238: 2233: 2227: 2218: 2213: 2207: 2206: 2200: 2191: 2185: 2180: 2174: 2167: 2161: 2137: 2128: 2119: 2110: 2104: 2103: 2071: 2065: 2063: 2060: 2046: 2043: 2040: 2037: 2034: 2031: 2028: 2025: 2022: 2019: 2016: 1996: 1993: 1988: 1984: 1963: 1938: 1934: 1930: 1926: 1922: 1919: 1916: 1913: 1910: 1907: 1904: 1901: 1896: 1892: 1888: 1883: 1879: 1875: 1853: 1849: 1845: 1842: 1837: 1833: 1829: 1824: 1820: 1797: 1793: 1770: 1766: 1762: 1758: 1754: 1751: 1748: 1745: 1742: 1739: 1736: 1733: 1728: 1724: 1720: 1717: 1714: 1694: 1691: 1688: 1685: 1680: 1676: 1661: 1652: 1649: 1626: 1623: 1622: 1621: 1609: 1604:is the set of 1596:In this case: 1571: 1568: 1567: 1566: 1558: 1539: 1497:is the set of 1473:Mathematician 1468:zero-sum games 1453: 1450: 1442: 1439: 1388: 1387: 1286: 1283: 1277: 1266: 1261: 1260: 1247: 1242: 1239: 1236: 1233: 1230: 1227: 1225: 1221: 1217: 1214: 1213: 1210: 1207: 1204: 1201: 1198: 1195: 1193: 1189: 1185: 1182: 1181: 1179: 1174: 1171: 1168: 1165: 1162: 1147: 1144: 1136: 1135: 1122: 1117: 1114: 1111: 1108: 1105: 1102: 1100: 1096: 1092: 1089: 1088: 1085: 1082: 1079: 1076: 1074: 1071: 1067: 1063: 1060: 1057: 1053: 1049: 1046: 1043: 1042: 1039: 1036: 1033: 1030: 1027: 1024: 1022: 1018: 1014: 1011: 1010: 1008: 1003: 1000: 997: 994: 991: 953: 950: 938: 937: 924: 919: 916: 913: 910: 907: 904: 902: 898: 894: 891: 890: 887: 884: 881: 878: 876: 873: 870: 867: 864: 859: 858: 855: 852: 849: 846: 843: 840: 838: 834: 830: 827: 826: 824: 819: 816: 813: 810: 807: 795:The function: 792: 789: 772: 769: 765: 761: 758: 755: 749: 746: 742: 738: 735: 732: 729: 726: 723: 720: 717: 714: 705:The function: 702: 699: 685: 682: 681: 680: 645: 642: 630: 627: 624: 621: 618: 615: 595: 575: 570: 566: 562: 559: 556: 551: 547: 526: 523: 518: 514: 493: 490: 485: 481: 457: 453: 450: 446: 440: 436: 432: 409: 405: 402: 398: 392: 388: 384: 347:) |  329: 326: 323:correspondence 310: 307: 304: 234: 229: 226: 225: 224: 209: 208: 207: 186: 148: 110: 107: 46:. It provides 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 4532: 4521: 4518: 4516: 4513: 4511: 4508: 4506: 4503: 4502: 4500: 4485: 4477: 4476: 4473: 4467: 4464: 4462: 4459: 4457: 4456:Weak topology 4454: 4452: 4449: 4447: 4444: 4442: 4439: 4438: 4436: 4432: 4425: 4421: 4418: 4416: 4413: 4411: 4408: 4406: 4403: 4401: 4398: 4396: 4393: 4391: 4388: 4386: 4383: 4381: 4380:Index theorem 4378: 4376: 4373: 4371: 4368: 4366: 4363: 4362: 4360: 4356: 4350: 4347: 4345: 4342: 4341: 4339: 4337:Open problems 4335: 4329: 4326: 4324: 4321: 4319: 4316: 4314: 4311: 4309: 4306: 4304: 4301: 4300: 4298: 4294: 4288: 4285: 4283: 4280: 4278: 4275: 4273: 4270: 4268: 4265: 4263: 4260: 4258: 4255: 4253: 4250: 4248: 4245: 4243: 4240: 4239: 4237: 4233: 4227: 4224: 4222: 4219: 4217: 4214: 4212: 4209: 4207: 4204: 4202: 4199: 4197: 4194: 4192: 4189: 4187: 4184: 4183: 4181: 4179: 4175: 4165: 4162: 4160: 4157: 4155: 4152: 4149: 4145: 4141: 4138: 4136: 4133: 4131: 4128: 4127: 4125: 4121: 4115: 4112: 4110: 4107: 4105: 4102: 4100: 4097: 4095: 4092: 4090: 4087: 4085: 4082: 4080: 4077: 4075: 4072: 4070: 4067: 4066: 4063: 4060: 4056: 4051: 4047: 4043: 4036: 4031: 4029: 4024: 4022: 4017: 4016: 4013: 4005: 4001: 4000: 3995: 3991: 3990: 3986: 3979: 3972: 3966: 3961: 3960: 3954: 3950: 3943: 3939: 3935: 3928: 3924: 3920: 3919: 3915: 3907: 3901: 3897: 3893: 3886: 3883: 3878: 3872: 3865: 3864: 3859: 3853: 3851: 3849: 3845: 3840: 3836: 3831: 3826: 3821: 3816: 3812: 3808: 3804: 3800: 3796: 3789: 3786: 3781: 3777: 3773: 3769: 3765: 3761: 3757: 3753: 3746: 3743: 3738: 3734: 3730: 3724: 3720: 3713: 3710: 3705: 3701: 3697: 3693: 3689: 3685: 3684: 3676: 3673: 3668: 3662: 3658: 3657: 3652: 3646: 3643: 3638: 3631: 3629: 3625: 3620: 3616: 3609: 3606: 3601: 3599:0-521-38808-2 3595: 3591: 3584: 3581: 3576: 3572: 3567: 3562: 3557: 3552: 3548: 3544: 3540: 3536: 3532: 3528: 3522: 3520: 3516: 3511: 3507: 3503: 3499: 3495: 3489: 3487: 3483: 3477: 3475: 3472: 3464: 3460: 3458: 3454: 3450: 3447: 3443: 3440: 3436: 3432: 3427: 3426: 3425: 3423: 3418: 3416: 3409: 3407: 3404: 3400: 3397: 3393: 3389: 3384: 3383: 3382: 3376: 3373: ∈  3372: 3368: 3364: 3360: 3356: 3352: 3348: 3344: 3340: 3337: 3334: 3331:} is open in 3330: 3326: 3322: 3318: 3315: ⊂  3314: 3311: 3308:if for every 3307: 3306: 3301: 3297: 3294: 3293: 3292: 3290: 3286: 3282: 3274: 3272: 3270: 3266: 3262: 3258: 3251: 3247: 3245: 3239: 3235: 3234:combinatorial 3231: 3228: 3224: 3223: 3222: 3220: 3216: 3214: 3205: 3201: 3198: 3196: 3194: 3190: 3186: 3182: 3178: 3157: 3153: 3148: 3139: 3135: 3131: 3126: 3122: 3114: 3110: 3106: 3103: 3097: 3094: 3090: 3086: 3081: 3077: 3072: 3064: 3060: 3056: 3051: 3047: 3039: 3035: 3031: 3028: 3022: 3018: 3015: 3008: 3007: 3006: 3004: 3000: 2994: 2992: 2988: 2984: 2980: 2976: 2972: 2968: 2964: 2957: 2954: 2953: 2949: 2945: 2941: 2937: 2933: 2929: 2928: 2927: 2924: 2922: 2918: 2914: 2910: 2906: 2897: 2893: 2888: 2884: 2879: 2875: 2870: 2866: 2862: 2858: 2855: 2854: 2853: 2850: 2846: 2841: 2837: 2832: 2830: 2826: 2822: 2818: 2814: 2810: 2806: 2802: 2798: 2794: 2790: 2786: 2782: 2778: 2775: 2770: 2766: 2761: 2757: 2752: 2748: 2743: 2739: 2735: 2731: 2727: 2722: 2718: 2713: 2709: 2704: 2700: 2695: 2691: 2687: 2680: 2677: 2676: 2675: 2671: 2667: 2661: 2657: 2651: 2647: 2641: 2637: 2629: 2623: 2619: 2616: 2613: 2609: 2603: 2599: 2596: 2594: 2588: 2584: 2581: 2578: 2574: 2568: 2564: 2561: 2560: 2559: 2557: 2553: 2550:) such that 2549: 2545: 2541: 2533: 2529: 2523: 2519: 2516: 2514: 2508: 2504: 2501: 2498: 2494: 2488: 2484: 2481: 2479: 2473: 2469: 2466: 2465: 2464: 2462: 2458: 2454: 2450: 2445: 2443: 2439: 2430: 2426: 2421: 2417: 2413: 2410: 2409: 2408: 2405: 2401: 2396: 2392: 2387: 2383: 2378: 2374: 2369: 2364: 2357: 2350: 2343: 2336: 2329: 2322: 2317: 2306: 2302: 2297: 2293: 2290: 2288: 2285: 2282: 2278: 2273: 2269: 2266: 2264: 2261: 2260: 2255: 2251: 2246: 2242: 2239: 2237: 2234: 2230: 2226: 2221: 2217: 2214: 2212: 2209: 2208: 2203: 2199: 2194: 2190: 2184: 2181: 2177: 2173: 2166: 2160: 2157: 2156: 2153: 2152: 2151: 2149: 2145: 2140: 2136: 2131: 2127: 2122: 2118: 2113: 2109: 2102: 2099: 2098: 2097: 2095: 2090: 2088: 2078: 2069: 2066: 2062:Proof outline 2061: 2058: 2041: 2035: 2032: 2029: 2023: 2020: 2017: 1994: 1986: 1982: 1961: 1952: 1936: 1932: 1928: 1917: 1911: 1908: 1902: 1894: 1890: 1886: 1881: 1877: 1851: 1847: 1843: 1835: 1831: 1822: 1818: 1795: 1791: 1768: 1764: 1760: 1749: 1743: 1740: 1734: 1726: 1722: 1715: 1712: 1692: 1686: 1683: 1678: 1674: 1660: 1658: 1648: 1646: 1642: 1638: 1632: 1625:Fair division 1624: 1618: 1614: 1610: 1607: 1603: 1600:The base set 1599: 1598: 1597: 1594: 1592: 1588: 1583: 1577: 1569: 1563: 1559: 1556: 1552: 1548: 1544: 1540: 1538: 1535: 1534: 1529: 1525: 1522: 1521: 1516: 1512: 1508: 1504: 1500: 1496: 1493:The base set 1492: 1491: 1490: 1488: 1484: 1480: 1476: 1471: 1469: 1465: 1459: 1451: 1448: 1440: 1438: 1436: 1432: 1431:metric spaces 1428: 1424: 1420: 1416: 1412: 1408: 1404: 1400: 1396: 1391: 1386: 1384: 1379: 1376: 1372: 1369: ∈  1368: 1365: 1361: 1357: 1354: 1351: 1348: 1346: 1343: 1337: 1333: 1330: 1326: 1323: 1322: 1318: 1315: 1311: 1307: 1302: 1299: 1296: 1295: 1294: 1292: 1284: 1282: 1280: 1273: 1269: 1240: 1237: 1234: 1231: 1228: 1223: 1219: 1215: 1208: 1205: 1202: 1199: 1196: 1191: 1187: 1183: 1177: 1172: 1166: 1160: 1153: 1152: 1151: 1145: 1143: 1141: 1115: 1112: 1109: 1106: 1103: 1098: 1094: 1090: 1083: 1080: 1077: 1069: 1065: 1061: 1058: 1055: 1051: 1047: 1037: 1034: 1031: 1028: 1025: 1020: 1016: 1012: 1006: 1001: 995: 989: 982: 981: 980: 977: 975: 971: 967: 958: 951: 949: 947: 943: 917: 914: 911: 908: 905: 900: 896: 892: 885: 882: 879: 871: 868: 865: 853: 850: 847: 844: 841: 836: 832: 828: 822: 817: 811: 805: 798: 797: 796: 790: 788: 786: 767: 763: 759: 756: 753: 747: 744: 740: 736: 733: 730: 724: 718: 712: 700: 695: 690: 683: 678: 674: 671: ∈  670: 666: 662: 658: 655: ∈  654: 650: 646: 643: 625: 619: 616: 613: 593: 568: 564: 557: 554: 549: 545: 524: 516: 512: 491: 483: 479: 451: 448: 438: 434: 403: 400: 390: 386: 374: 370: 367: ×  366: 362: 358: 354: 351: ∈  350: 346: 342: 339:if the set {( 338: 334: 330: 327: 324: 308: 305: 302: 294: 290: 286: 282: 279:, written as 278: 274: 270: 266: 262: 258: 254: 250: 246: 243:from the set 242: 239: 235: 232: 231: 227: 223: 221: 216: 213: 210: 205: 202: ∈  201: 198: 194: 190: 187: 185: 182: 178: 175: 174: 173: 170: 167: 165: 159: 155: 152: 149: 146: 143: 142: 138: 135: 131: 127: 122: 119: 116: 115: 114: 108: 106: 104: 100: 96: 92: 88: 83: 81: 77: 73: 69: 65: 61: 57: 53: 49: 45: 41: 37: 33: 19: 4446:Balanced set 4420:Distribution 4358:Applications 4211:Krein–Milman 4196:Closed graph 3997: 3958: 3941: 3926: 3895: 3885: 3869:. Springer. 3862: 3802: 3798: 3788: 3780:the original 3759: 3755: 3745: 3718: 3712: 3687: 3683:Econometrica 3681: 3675: 3655: 3645: 3636: 3618: 3608: 3589: 3583: 3541:(1): 48–49. 3538: 3534: 3501: 3497: 3468: 3457:fixed points 3428: 3419: 3412: 3385: 3380: 3374: 3370: 3366: 3363:Kakutani map 3362: 3358: 3354: 3353:and φ:  3346: 3342: 3338:Kakutani map 3332: 3328: 3324: 3320: 3316: 3312: 3303: 3299: 3278: 3264: 3260: 3256: 3254: 3249: 3243: 3218: 3212: 3209: 3203: 3199: 3192: 3188: 3184: 3180: 3176: 3174: 2998: 2995: 2990: 2986: 2982: 2978: 2974: 2970: 2966: 2962: 2960: 2955: 2947: 2943: 2939: 2935: 2931: 2925: 2920: 2916: 2912: 2908: 2904: 2902: 2895: 2891: 2886: 2882: 2877: 2873: 2868: 2864: 2860: 2856: 2848: 2844: 2839: 2835: 2833: 2828: 2824: 2820: 2816: 2812: 2808: 2804: 2800: 2796: 2792: 2788: 2784: 2768: 2764: 2759: 2755: 2750: 2746: 2741: 2737: 2720: 2716: 2711: 2707: 2702: 2698: 2693: 2689: 2683: 2678: 2669: 2665: 2659: 2655: 2649: 2645: 2639: 2635: 2633: 2627: 2621: 2617: 2611: 2607: 2601: 2597: 2592: 2586: 2582: 2576: 2572: 2566: 2562: 2555: 2551: 2547: 2543: 2539: 2537: 2531: 2527: 2521: 2517: 2512: 2506: 2502: 2496: 2492: 2486: 2482: 2477: 2471: 2467: 2460: 2456: 2455:) such that 2452: 2448: 2446: 2437: 2435: 2428: 2424: 2419: 2415: 2411: 2403: 2399: 2394: 2390: 2385: 2381: 2376: 2372: 2370: 2362: 2355: 2348: 2341: 2334: 2327: 2320: 2318: 2314: 2304: 2300: 2295: 2291: 2286: 2280: 2276: 2271: 2267: 2262: 2253: 2249: 2244: 2240: 2235: 2228: 2224: 2219: 2215: 2210: 2201: 2197: 2192: 2188: 2182: 2175: 2171: 2164: 2158: 2143: 2138: 2134: 2129: 2125: 2120: 2116: 2111: 2107: 2105: 2100: 2091: 2084: 2067: 1953: 1665: 1654: 1634: 1616: 1612: 1601: 1595: 1579: 1554: 1550: 1546: 1542: 1536: 1532: 1531: 1527: 1523: 1519: 1518: 1510: 1506: 1494: 1472: 1461: 1441:Applications 1434: 1425:. Since all 1422: 1418: 1414: 1410: 1406: 1402: 1401:range space 1392: 1389: 1380: 1377: 1374: 1370: 1366: 1363: 1359: 1355: 1352: 1349: 1339: 1335: 1331: 1328: 1324: 1303: 1300: 1297: 1288: 1275: 1271: 1264: 1262: 1149: 1139: 1137: 978: 973: 969: 965: 963: 945: 941: 939: 794: 784: 704: 693: 676: 672: 668: 664: 660: 656: 652: 648: 647:Let φ:  368: 364: 356: 352: 348: 344: 340: 337:closed graph 336: 332: 328:Closed graph 322: 292: 288: 284: 280: 276: 268: 260: 256: 252: 248: 244: 240: 237: 217: 214: 211: 203: 199: 196: 192: 188: 184: 181:closed graph 176: 171: 168: 161: 157: 153: 150: 144: 123: 120: 117: 112: 84: 58:subset of a 35: 29: 4375:Heat kernel 4365:Hardy space 4272:Trace class 4186:Hahn–Banach 4148:Topological 3981:economics.) 3944:. Springer. 3471:Ken Binmore 3429:Let S be a 3386:Let S be a 3319:, the set { 2834:But since ( 2777:subsequence 2730:compact set 1479:game theory 1458:Game theory 1452:Game theory 1383:fixed point 661:fixed point 644:Fixed point 247:to the set 228:Definitions 220:fixed point 99:game theory 64:fixed point 4499:Categories 4308:C*-algebra 4123:Properties 3478:References 3248:Arbitrary 3215:-simplices 2774:convergent 1810:such that 1705:such that 1629:See also: 1574:See also: 1456:See also: 1445:See also: 1270:= 0.5 - 1/ 606:, we have 471:such that 363:subset of 255:points in 62:to have a 4282:Unbounded 4277:Transpose 4235:Operators 4164:Separable 4159:Reflexive 4144:Algebraic 4130:Barrelled 4004:EMS Press 3737:984777840 3431:non-empty 3422:Euclidean 3403:Hausdorff 3388:non-empty 3323:| φ( 3158:∗ 3140:∗ 3132:− 3127:∗ 3115:∗ 3107:− 3098:− 3082:∗ 3065:∗ 3057:− 3052:∗ 3040:∗ 3032:− 2981:*. Since 2907:* equals 2881:) = lim ( 2872:) − (lim 2863:* = (lim 2333:= 1. Let 2042:φ 2036:⁡ 2030:∈ 1992:→ 1918:φ 1912:⁡ 1903:∈ 1750:φ 1744:⁡ 1735:⊂ 1716:⁡ 1690:→ 1637:envy-free 1560:Then the 1475:John Nash 1399:Hausdorff 1306:non-empty 1238:≤ 1232:≤ 1200:≤ 1161:φ 1113:≤ 1029:≤ 990:φ 915:≤ 845:≤ 806:φ 757:− 734:− 713:φ 620:ϕ 617:∈ 558:ϕ 555:∈ 522:→ 489:→ 452:∈ 404:∈ 306:∈ 273:power set 126:non-empty 109:Statement 103:economics 91:John Nash 4484:Category 4296:Algebras 4178:Theorems 4135:Complete 4104:Schwartz 4050:glossary 3925:(1989). 3839:16589065 3653:(1997). 3617:(1994). 3575:16588946 3529:(1950). 3465:Anecdote 3310:open set 3206:-simplex 3183:) since 2326:= 0 and 2148:sequence 1319:of some 684:Examples 586:for all 359:)} is a 265:function 139:of some 76:topology 4287:Unitary 4267:Nuclear 4252:Compact 4247:Bounded 4242:Adjoint 4216:Min–max 4109:Sobolev 4094:Nuclear 4084:Hilbert 4079:Fréchet 4044: ( 4006:, 2001 3830:1063516 3807:Bibcode 3776:2032478 3704:1907539 3566:1063129 3543:Bibcode 3435:compact 3392:compact 2969:* then 2911:*. Let 2807:*) and 2007:. Then 1565:exists. 1409::  1334::  1310:compact 1281:= 3/4. 1142:= 0.5. 371:in the 283::  271:to the 253:or more 156::  130:compact 56:compact 4262:Normal 4099:Orlicz 4089:Hölder 4069:Banach 4058:Spaces 4046:topics 3967:  3902:  3873:  3837:  3827:  3774:  3735:  3725:  3702:  3663:  3596:  3573:  3563:  3444:of a 3442:subset 3439:convex 3424:case: 3399:subset 3396:convex 3302:→2 is 3289:Ky Fan 3187:* and 3003:convex 2985:* ∈ φ( 2946:* ∈ φ( 2899:) = 0. 2811:* ∈ φ( 2803:* ∈ φ( 2442:convex 2205:) ≤ 2 2142:) for 2074:": --> 1954:Since 1606:tuples 1587:Walras 1526:Then, 1499:tuples 1433:) and 1381:has a 1340:be an 1317:subset 1314:convex 751:  361:closed 218:has a 177:φ has 137:subset 134:convex 68:mapped 52:convex 34:, the 4074:Besov 3772:JSTOR 3700:JSTOR 3401:of a 3202:is a 3001:) is 2436:Then 2170:> 2106:Let ( 2033:graph 1909:graph 1866:, so 1741:graph 1713:graph 1663:Proof 1304:be a 659:is a 267:from 162:be a 124:be a 38:is a 4422:(or 4140:Dual 3965:ISBN 3900:ISBN 3871:ISBN 3835:PMID 3733:OCLC 3723:ISBN 3661:ISBN 3594:ISBN 3571:PMID 3437:and 3394:and 3345:and 3341:Let 3287:and 3005:and 2973:* = 2965:* = 2938:* ≤ 2934:) ∋ 2919:* = 2903:So, 2859:* − 2827:* ≤ 2819:* ≥ 2664:and 2546:∈ φ( 2451:∈ φ( 2432:)/2. 2398:and 2248:∈ φ( 2223:∈ φ( 2179:≥ 0 2163:1 ≥ 2076:edit 1639:and 1553:, φ( 1375:Then 1312:and 1206:< 1107:< 1035:< 909:< 851:< 696:(x)= 537:and 423:and 212:Then 132:and 101:and 42:for 3825:PMC 3815:doi 3764:doi 3692:doi 3561:PMC 3551:doi 3506:doi 3349:be 3283:by 2989:), 2961:If 2923:*. 2831:*. 2787:*, 2779:by 2732:by 2414:= ( 1580:In 1517:in 1501:of 1338:→2 1329:Let 1298:Let 1274:, 1229:0.5 1209:0.5 1104:0.5 1084:0.5 1038:0.5 906:0.5 886:0.5 854:0.5 667:if 663:of 275:of 151:Let 118:Let 30:In 4501:: 4048:– 4002:, 3996:, 3894:. 3847:^ 3833:. 3823:. 3813:. 3803:38 3801:. 3797:. 3770:. 3758:. 3754:. 3731:. 3698:. 3688:22 3686:. 3627:^ 3569:. 3559:. 3549:. 3539:36 3537:. 3533:. 3518:^ 3500:. 3485:^ 3433:, 3417:. 3390:, 2977:= 2950:). 2942:≤ 2930:φ( 2915:= 2890:− 2843:− 2795:*, 2791:*, 2763:, 2754:, 2745:, 2715:, 2706:, 2697:, 2672:+1 2662:+1 2654:, 2652:+1 2644:, 2642:+1 2626:= 2624:+1 2606:= 2604:+1 2591:= 2589:+1 2571:= 2569:+1 2554:≤ 2526:= 2524:+1 2511:= 2509:+1 2491:= 2489:+1 2476:= 2474:+1 2459:≥ 2444:. 2389:, 2380:, 2368:. 2299:≤ 2287:6. 2275:≥ 2263:5. 2257:) 2236:4. 2232:) 2211:3. 2196:− 2183:2. 2159:1. 2133:, 2124:, 2115:, 2070:= 1951:. 1659:: 1647:. 1593:. 1373:. 1362:) 1347:on 1327:. 1308:, 679:). 504:, 236:A 195:) 179:a 166:on 128:, 105:. 54:, 4426:) 4150:) 4146:/ 4142:( 4052:) 4034:e 4027:t 4020:v 3973:. 3908:. 3879:. 3841:. 3817:: 3809:: 3766:: 3760:3 3739:. 3706:. 3694:: 3669:. 3602:. 3577:. 3553:: 3545:: 3512:. 3508:: 3502:8 3377:. 3375:X 3371:x 3367:x 3359:Y 3355:X 3347:Y 3343:X 3335:. 3333:X 3329:W 3325:x 3321:x 3317:Y 3313:W 3300:X 3265:S 3261:S 3257:S 3250:S 3219:n 3213:n 3204:n 3200:S 3193:x 3189:q 3185:p 3181:x 3177:x 3154:q 3149:) 3136:q 3123:p 3111:q 3104:x 3095:1 3091:( 3087:+ 3078:p 3073:) 3061:q 3048:p 3036:q 3029:x 3023:( 3019:= 3016:x 2999:x 2991:x 2987:x 2983:p 2979:q 2975:x 2971:p 2967:q 2963:p 2948:x 2944:p 2940:x 2936:q 2932:x 2921:a 2917:b 2913:x 2909:a 2905:b 2896:n 2892:a 2887:n 2883:b 2878:n 2874:a 2869:n 2865:b 2861:a 2857:b 2849:i 2845:a 2840:i 2836:b 2829:b 2825:q 2821:a 2817:p 2813:b 2809:q 2805:a 2801:p 2797:q 2793:b 2789:p 2785:a 2769:n 2765:q 2760:n 2756:b 2751:n 2747:p 2742:n 2738:a 2721:n 2717:q 2712:n 2708:b 2703:n 2699:p 2694:n 2690:a 2670:k 2666:q 2660:k 2656:p 2650:k 2646:b 2640:k 2636:a 2630:. 2628:s 2622:k 2618:q 2612:k 2608:p 2602:k 2598:p 2593:m 2587:k 2583:b 2577:k 2573:a 2567:k 2563:a 2556:m 2552:s 2548:m 2544:s 2540:m 2532:k 2528:q 2522:k 2518:q 2513:r 2507:k 2503:p 2497:k 2493:b 2487:k 2483:b 2478:m 2472:k 2468:a 2461:m 2457:r 2453:m 2449:r 2438:m 2429:k 2425:b 2423:+ 2420:k 2416:a 2412:m 2404:k 2400:q 2395:k 2391:p 2386:k 2382:b 2377:k 2373:a 2366:0 2363:q 2359:0 2356:p 2352:0 2349:p 2345:0 2342:q 2338:0 2335:p 2331:0 2328:b 2324:0 2321:a 2305:i 2301:b 2296:i 2292:q 2281:i 2277:a 2272:i 2268:p 2254:i 2250:b 2245:i 2241:q 2229:i 2225:a 2220:i 2216:p 2202:i 2198:a 2193:i 2189:b 2187:( 2176:i 2172:a 2168:i 2165:b 2144:i 2139:i 2135:q 2130:i 2126:p 2121:i 2117:b 2112:i 2108:a 2080:] 2068:S 2045:) 2039:( 2027:) 2024:x 2021:, 2018:x 2015:( 1995:x 1987:n 1983:x 1962:S 1937:n 1933:/ 1929:1 1925:] 1921:) 1915:( 1906:[ 1900:) 1895:n 1891:x 1887:, 1882:n 1878:x 1874:( 1852:n 1848:x 1844:= 1841:) 1836:n 1832:x 1828:( 1823:n 1819:f 1796:n 1792:x 1769:n 1765:/ 1761:1 1757:] 1753:) 1747:( 1738:[ 1732:) 1727:n 1723:f 1719:( 1693:S 1687:S 1684:: 1679:n 1675:f 1617:x 1613:x 1602:S 1555:x 1551:x 1547:x 1543:x 1537:. 1533:R 1528:S 1524:. 1520:R 1511:k 1507:k 1495:S 1435:φ 1423:x 1419:x 1417:( 1415:φ 1411:X 1407:φ 1403:Y 1385:. 1378:φ 1371:S 1367:x 1360:x 1358:( 1356:φ 1350:S 1336:S 1332:φ 1325:R 1301:S 1278:n 1276:y 1272:n 1267:n 1265:x 1241:1 1235:x 1224:4 1220:/ 1216:1 1203:x 1197:0 1192:4 1188:/ 1184:3 1178:{ 1173:= 1170:) 1167:x 1164:( 1140:x 1116:1 1110:x 1099:4 1095:/ 1091:1 1081:= 1078:x 1073:} 1070:4 1066:/ 1062:1 1059:, 1056:4 1052:/ 1048:3 1045:{ 1032:x 1026:0 1021:4 1017:/ 1013:3 1007:{ 1002:= 999:) 996:x 993:( 974:x 970:x 968:( 966:φ 946:x 942:x 918:1 912:x 901:4 897:/ 893:1 883:= 880:x 875:] 872:1 869:, 866:0 863:[ 848:x 842:0 837:4 833:/ 829:3 823:{ 818:= 815:) 812:x 809:( 785:x 771:] 768:4 764:/ 760:x 754:1 748:, 745:2 741:/ 737:x 731:1 728:[ 725:= 722:) 719:x 716:( 694:φ 677:a 675:( 673:φ 669:a 665:φ 657:X 653:a 649:X 641:. 629:) 626:x 623:( 614:y 594:n 574:) 569:n 565:x 561:( 550:n 546:y 525:y 517:n 513:y 492:x 484:n 480:x 456:N 449:n 445:} 439:n 435:y 431:{ 408:N 401:n 397:} 391:n 387:x 383:{ 369:Y 365:X 357:x 355:( 353:φ 349:y 345:y 343:, 341:x 333:X 309:X 303:x 293:x 291:( 289:φ 285:X 281:φ 277:Y 269:X 261:X 257:Y 249:Y 245:X 241:φ 222:. 215:φ 206:. 204:S 200:x 193:x 191:( 189:φ 183:; 169:S 158:S 154:φ 147:. 145:R 121:S 20:)

Index

Kakutani fixed point theorem
mathematical analysis
fixed-point theorem
set-valued functions
sufficient conditions
convex
compact
Euclidean space
fixed point
mapped
Brouwer fixed point theorem
topology
continuous functions
Shizuo Kakutani
John Nash
Nash equilibria
game theory
economics
non-empty
compact
convex
subset
Euclidean space
set-valued function
closed graph
fixed point
function
power set
closed
product topology

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