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Perfect Bayesian equilibrium

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108:. Perfect Bayesian equilibria are used to solve the outcome of games where players take turns but are unsure of the "type" of their opponent, which occurs when players don't know their opponent's preference between individual moves. A classic example of a dynamic game with types is a war game where the player is unsure whether their opponent is a risk-taking " 1184:
Now, suppose that this game is repeated two times. The two plays are independent, i.e., each day the players decide simultaneously whether to build a public good in that day, get a payoff of 1 if the good is built in that day, and pay their cost if they built in that day. The only connection between
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Note that option 3 is a Nash equilibrium. If we ignore beliefs, then rejecting can be considered a best-response for the receiver, since it does not affect their payoff (since there is no gift anyway). Moreover, option 3 is even a SPE, since the only subgame here is the entire game. Such implausible
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To summarize: in this variant of the gift game, there are two SPEs: either the sender always gives and the receiver always accepts, or the sender always does not give and the receiver always rejects. From these, only the first one is a PBE; the other is not a PBE since it cannot be supported by any
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must contain complete information sets, sometimes there is only one subgame—the entire game—and so every Nash equilibrium is trivially subgame perfect. Even if a game does have more than one subgame, the inability of subgame perfection to cut through information sets can result in implausible
1181:, then there is a symmetric equilibrium in which the threshold cost of both players is 2/3. This means that a player whose cost is between 2/3 and 1 will not contribute, even though their cost is below the benefit, because of the possibility that the other player will contribute. 1582:
willing to build than in the one-stage game. Intuitively, the reason is that, when a player does not contribute in the first day, they make the other player believe their cost is high, and this makes the other player more willing to contribute in the second day.
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so the sender is very likely a friend, but the receiver still would refuse any gift because he thinks enemies are much more likely than friends to give gifts. This shows how pessimistic beliefs can result in an equilibrium bad for both players, one that is not
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In the one-stage game, each player builds if-and-only-if their cost is smaller than their expected gain from building. The expected gain from building is exactly 1 times the probability that the other player does NOT build. In equilibrium, for every player
1599:- some bidders raise the current price much more than the minimal increment. One explanation to this is that it serves as a signal to the other bidders. There is a PBE in which each bidder jumps if-and-only-if their value is above a certain threshold. See 674:
if an enemy. The receiver's beliefs are updated accordingly: if he receives a gift, he believes the sender is an enemy; otherwise, he believes the sender is a friend. The receiver's best-response strategy is
1308:. They update their belief accordingly, and conclude that there is a smaller chance that their opponent will build in day 2. Therefore, they increase their threshold cost, and the threshold cost in day 2 is 1382:. They update their belief accordingly, and conclude that there is a larger chance that their opponent will build in day 2. Therefore, they decrease their threshold cost, and the threshold cost in day 2 is 650:
if an enemy. The receiver's beliefs are updated accordingly: if he receives a gift, he believes the sender is a friend; otherwise, he believes the sender is an enemy. Thus, the receiver will respond with
1699: 561:, since both types take that action and it is uninformative about the sender's type in this equilibrium. The out-of-equilibrium belief does not matter, since the sender would not want to deviate to 557:
The sender prefers the payoff of 1 from giving to the payoff of 0 from not giving, expecting that his gift will be accepted. In equilibrium, Bayes's Rule requires the receiver to have the belief
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of a player in a given information set specifies his choice of action in that information set, which may depend on the history (on actions taken previously in the game). This is similar to a
1057:- each player knows their own cost but not the other's cost. It is only known that each cost is drawn independently at random from some probability distribution. This makes this game a 703:
In the following example, the set of PBEs is strictly smaller than the set of SPEs and BNEs. It is a variant of the above gift-game, with the following change to the receiver's utility:
1422: 1348: 436: 1518:) in each of these situations. Since the threshold player should be indifferent between contributing and not contributing, it is possible to calculate the day-1 threshold cost 733:
The sender's strategy is: always give. The receiver's beliefs are not updated: they still believe in the a-priori probability, that the sender is a friend with probability
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of the other players. Formally, a belief system is an assignment of probabilities to every node in the game such that the sum of probabilities in any information set is 1.
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the games is that, by playing in the first day, the players may reveal some information about their costs, and this information might affect the play in the second day.
1147: 1115: 595: 506: 348: 465: 624: 1576: 1051: 777: 248: 552: 292: 1083: 1024: 892: 840: 820: 797: 751: 222: 1179: 872: 1275:, we work backwards and analyze the players' actions in day 2. Their actions depend on the history (= the two actions in day 1), and there are three options: 1149:. This threshold cost can be calculated based on the probability distribution of the players' costs. For example, if the costs are distributed uniformly on 1485:. There is an equilibrium in which the actions in day 2 are identical to the actions in day 1 - player 1 builds and player 2 does not build. 802:
The sender's strategy is: never give. Suppose the receiver's beliefs when receiving a gift is that the sender is a friend with probability
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at all. That belief must be pessimistic enough that the receiver prefers the payoff of 0 from rejecting a gift to the expected payoff of
631:. These beliefs seem unrealistic, though, and game theorists are often willing to reject some perfect Bayesian equilibria as implausible. 150:
of a player in a given information set determines what node in that information set he believes the game has reached. The belief may be a
894:, the receiver's optimal strategy is: accept. This is NOT a PBE, since the sender can improve their payoff from 0 to 1 by giving a gift. 2841: 438:
from accepting, so the requirement that the receiver's strategy maximize his expected payoff given his beliefs necessitates that
1615:- a refinement of PBE, that restricts the beliefs that can be assigned to off-equilibrium information sets to "reasonable" ones. 1774: 96:(PBE) is a solution with Bayesian probability to a turn-based game with incomplete information. More specifically, it is an 2678: 638:, in which the two types of sender choose different actions, and see why they do not exist as perfect Bayesian equilibria: 2495: 2025: 1823: 729:
Similarly to example 1, there is no separating equilibrium. Let's look at the following potential pooling equilibria:
1674: 2314: 2133: 1737: 931:. See also for more examples. There is a recent application of this concept in Poker, by Loriente and Diez (2023). 1930: 1427:
In day 1, exactly one player built; suppose it is player 1. So now, it is known that the cost of player 1 is below
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the threshold cost of both players in day 1 (so in day 1, each player builds if-and-only-if their cost is at most
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The sender prefers the payoff of 0 from not giving to the payoff of -1 from sending and not being accepted. Thus,
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The sender's utility is 1 if his gift is accepted, -1 if his gift is rejected, and 0 if he does not give any gift.
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is required by Bayes's Rule, since both types take that action and it is uninformative about the sender's type.
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The sender's strategy is: never give, and the receiver's strategy is: reject. This is NOT a PBE, since for
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Equilibria 1 and 2 are the only equilibria that might exist, but we can also check for the two potential
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equilibria might arise also in games with complete information, but they may be eliminated by applying
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on every path reached in equilibrium with positive probability. On paths of zero probability, known as
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It is possible to calculate the expected payoff of the "threshold player" (a player with cost exactly
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over the nodes in the information set, and is typically a probability distribution over the possible
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is a sequence of simultaneous games played one after the other. These games may be identical (as in
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or not build. Each player gains 1 if the public good is built and 0 if not; in addition, if player
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If the sender is a friend, then the receiver's utility is 1 (if they accept) or 0 (if they reject).
175:: each belief should be updated according to the equilibrium strategies, the observed actions, and 151: 2593: 265:
If the sender is an enemy, then the receiver's utility is -1 (if he accepts) or 0 (if he rejects).
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If the sender is a friend, then the receiver's utility is 1 (if he accepts) or 0 (if he rejects).
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In day 1, both players built. So now both players know that their opponent's cost is below
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The receiver has only one type, and two strategies: either accept the gift, or reject it.
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In day 1, no player built. So now both players know that their opponent's cost is above
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has zero probability in equilibrium and Bayes's Rule does not restrict the belief
2713: 2673: 2628: 2543: 2538: 2259: 2211: 2093: 1858: 1828: 1798: 1592: 910:. However, Bayesian games often contain non-singleton information sets and since 140: 2578: 2653: 2643: 2633: 2568: 2558: 2548: 2533: 2329: 2309: 2294: 2289: 2249: 2216: 2201: 2196: 2186: 1990: 1715: 1626: 176: 80: 2835: 2693: 2683: 2638: 2623: 2603: 2374: 2349: 2221: 2191: 2181: 2168: 2068: 2010: 1945: 1878: 1058: 944: 70: 2668: 2663: 2518: 2088: 1596: 101: 1117:, such that the player contributes if-and-only-if their cost is less than 2785: 2588: 2583: 2563: 2359: 2344: 2153: 2123: 2053: 2043: 1873: 1808: 1784: 1719: 89: 31: 1752: 687:, to increase his payoff from -1 to 0, so this cannot be an equilibrium. 2414: 2063: 799:). This is a PBE - it is a best-response for both sender and receiver. 663:, to increase his payoff from 0 to 1, so this cannot be an equilibrium. 204:
The sender has two possible types: either a "friend" (with probability
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The strategies and beliefs also must satisfy the following conditions:
2319: 2239: 2058: 1729: 113: 109: 169:: each strategy should be optimal in expectation, given the beliefs. 2754: 2254: 2475: 2465: 2143: 911: 250:). Each type has two strategies: either give a gift, or not give. 519:, whether they are the friend type or the enemy type. Receiver: 309:, whether they are the friend type or the enemy type. Receiver: 2244: 187:
A perfect Bayesian equilibrium is always a Nash equilibrium.
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that uses Bayesian updating to describe player behavior in
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If the sender is an enemy, then the receiver's utility is
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belief of the receiver, rejecting is not a best-response.
116:" type. Perfect Bayesian Equilibria are a refinement of 298:
in which both types of sender choose the same action:
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Any perfect Bayesian equilibrium has two components --
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The receiver's utility depends on who gives the gift:
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Loriente, Martín Iñaki & Diez, Juan Cruz (2023).
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The following game is a simple representation of the
880: 848: 828: 808: 785: 759: 739: 603: 574: 537: 480: 447: 367: 327: 277: 230: 210: 183:, the beliefs must be specified but can be arbitrary. 1026:builds the public good, they have to pay a cost of 565:no matter what response the receiver would have. 1570: 1539: 1510: 1477: 1448: 1416: 1374: 1342: 1300: 1267: 1238: 1209: 1173: 1141: 1109: 1077: 1045: 1018: 886: 866: 834: 814: 791: 771: 745: 618: 589: 546: 500: 459: 430: 342: 286: 242: 216: 722:Note that in this variant, accepting is a weakly 683:, though, the enemy sender will deviate to   659:, though, the enemy sender will deviate to   2833: 1714: 1188:We are looking for a symmetric PBE. Denote by 1768: 1700:"Perfect Bayesian Equilibrium in Kuhn Poker" 950: 934: 1775: 1761: 1782: 1672: 1625:- other refinements of PBE, specific to 691:We conclude that in this game, there is 191:Examples of perfect Bayesian equilibria 2834: 1710: 1708: 1646: 1547:. It turns out that this threshold is 1756: 1417:{\displaystyle c^{11}<{\hat {c}}} 1343:{\displaystyle c^{00}>{\hat {c}}} 431:{\displaystyle x(1)+(1-x)(-1)=2x-1,} 1705: 13: 1824:First-player and second-player win 1456:and the cost of player 2 is above 666:Suppose the sender's strategy is: 642:Suppose the sender's strategy is: 224:) or an "enemy" (with probability 14: 2858: 915:equilibria not being eliminated. 2842:Game theory equilibrium concepts 1931:Coalition-proof Nash equilibrium 922: 908:subgame perfect Nash equilibrium 1586: 16:Solution concept in game theory 1941:Evolutionarily stable strategy 1692: 1675:"Perfect Bayesian Equilibrium" 1666: 1649:"Perfect Bayesian Equilibrium" 1640: 1531: 1502: 1469: 1440: 1408: 1366: 1334: 1292: 1259: 1230: 1201: 1168: 1156: 861: 849: 753:and an enemy with probability 698: 407: 398: 395: 383: 377: 371: 195: 1: 1869:Simultaneous action selection 1702:. Universidad de San Andres. 1633: 568:Equilibrium 1 is perverse if 200:Consider the following game: 2806:List of games in game theory 1981:Quantal response equilibrium 1971:Perfect Bayesian equilibrium 1906:Bayes correlated equilibrium 1728:. Cambridge, Massachusetts: 1085:, there is a threshold cost 94:Perfect Bayesian Equilibrium 22:Perfect Bayesian Equilibrium 7: 2275:Optional prisoner's dilemma 2001:Self-confirming equilibrium 1606: 655:. If the receiver chooses 10: 2863: 2740:Principal variation search 2456:Aumann's agreement theorem 2119:Strategy-stealing argument 2026:Trembling hand equilibrium 1956:Markov perfect equilibrium 1951:Mertens-stable equilibrium 1680:. University of California 1540:{\displaystyle {\hat {c}}} 1511:{\displaystyle {\hat {c}}} 1478:{\displaystyle {\hat {c}}} 1449:{\displaystyle {\hat {c}}} 1375:{\displaystyle {\hat {c}}} 1301:{\displaystyle {\hat {c}}} 1268:{\displaystyle {\hat {c}}} 1239:{\displaystyle {\hat {c}}} 1210:{\displaystyle {\hat {c}}} 927:For further examples, see 313:, with the beliefs that 2776:Combinatorial game theory 2763: 2722: 2504: 2448: 2435:Princess and monster game 2230: 2132: 2034: 1986:Quasi-perfect equilibrium 1911:Bayesian Nash equilibrium 1892: 1791: 1142:{\displaystyle C_{i}^{*}} 1110:{\displaystyle C_{i}^{*}} 989: 951:Repeated public-good game 590:{\displaystyle p\geq .5.} 531:, choosing any value for 529:Prob(Friend|Not give) = x 501:{\displaystyle p\geq 1/2} 469:Prob(Friend|Not give) = p 343:{\displaystyle x\leq .5.} 315:Prob(Friend|Not Give) = p 118:Bayesian Nash equilibrium 76: 65: 57: 52: 47:Bayesian Nash equilibrium 42: 37: 26: 21: 2791:Evolutionary game theory 2524:Antoine Augustin Cournot 2410:Guess 2/3 of the average 2207:Strictly determined game 1996:Satisfaction equilibrium 1814:Escalation of commitment 935:PBE in multi-stage games 695:separating equilibrium. 679:If the receiver chooses 460:{\displaystyle \leq .5.} 294:Equilibrium 1 exists, a 152:probability distribution 112:" type or a pacifistic " 2796:Glossary of game theory 2395:Stackelberg competition 2016:Strong Nash equilibrium 1654:. Ohio State University 929:signaling game#Examples 2821:Tragedy of the commons 2801:List of game theorists 2781:Confrontation analysis 2491:Sprague–Grundy theorem 2006:Sequential equilibrium 1926:Correlated equilibrium 1613:Sequential equilibrium 1601:Jump bidding#signaling 1572: 1541: 1512: 1479: 1450: 1418: 1376: 1344: 1302: 1269: 1240: 1211: 1175: 1143: 1111: 1079: 1047: 1020: 888: 868: 836: 816: 793: 773: 747: 620: 619:{\displaystyle p=.99,} 591: 548: 523:with the beliefs that 502: 461: 432: 344: 319:Prob(Friend|Give) = x, 288: 244: 218: 167:Sequential rationality 106:incomplete information 2847:Non-cooperative games 2594:Jean-François Mertens 1573: 1571:{\displaystyle c^{*}} 1542: 1513: 1480: 1451: 1419: 1377: 1345: 1303: 1270: 1241: 1212: 1176: 1144: 1112: 1080: 1048: 1046:{\displaystyle C_{i}} 1021: 889: 869: 837: 817: 794: 774: 748: 636:separating equilibria 621: 592: 559:Prob(Friend|Give) = p 549: 525:Prob(Friend|Give) = p 503: 462: 433: 345: 289: 245: 219: 181:off-equilibrium paths 2723:Search optimizations 2599:Jennifer Tour Chayes 2486:Revelation principle 2481:Purification theorem 2420:Nash bargaining game 2385:Bertrand competition 2370:El Farol Bar problem 2335:Electronic mail game 2300:Lewis signaling game 1839:Hierarchy of beliefs 1555: 1522: 1493: 1460: 1431: 1386: 1357: 1312: 1283: 1250: 1221: 1192: 1153: 1121: 1089: 1069: 1030: 1010: 878: 846: 826: 806: 783: 757: 737: 714:(if they accept) or 601: 597:The game could have 572: 535: 478: 445: 365: 325: 275: 228: 208: 2771:Bounded rationality 2390:Cournot competition 2340:Rock paper scissors 2315:Battle of the sexes 2305:Volunteer's dilemma 2177:Perfect information 2104:Dominant strategies 1936:Epsilon-equilibrium 1819:Extensive-form game 1619:Intuitive criterion 1138: 1106: 1055:private information 772:{\displaystyle 1-p} 467:On the other hand, 296:pooling equilibrium 243:{\displaystyle 1-p} 98:equilibrium concept 2750:Paranoid algorithm 2730:Alpha–beta pruning 2609:John Maynard Smith 2440:Rendezvous problem 2280:Traveler's dilemma 2270:Gift-exchange game 2265:Prisoner's dilemma 2182:Large Poisson game 2149:Bargaining problem 2049:Backward induction 2021:Subgame perfection 1976:Proper equilibrium 1623:Divine equilibrium 1591:In an open-outcry 1568: 1537: 1508: 1475: 1446: 1414: 1372: 1340: 1298: 1265: 1236: 1207: 1171: 1139: 1124: 1107: 1092: 1075: 1043: 1016: 1000:free-rider problem 884: 864: 832: 812: 789: 769: 743: 726:for the receiver. 616: 587: 547:{\displaystyle x.} 544: 498: 457: 428: 340: 287:{\displaystyle p,} 284: 240: 214: 2829: 2828: 2735:Aspiration window 2704:Suzanne Scotchmer 2659:Oskar Morgenstern 2554:Donald B. Gillies 2496:Zermelo's theorem 2425:Induction puzzles 2380:Fair cake-cutting 2355:Public goods game 2285:Coordination game 2159:Intransitive game 2084:Forward induction 1966:Pareto efficiency 1946:Gibbs equilibrium 1916:Berge equilibrium 1864:Simultaneous game 1534: 1505: 1472: 1443: 1411: 1369: 1337: 1295: 1262: 1233: 1204: 1078:{\displaystyle i} 1019:{\displaystyle i} 996: 995: 887:{\displaystyle q} 842:is any number in 835:{\displaystyle q} 815:{\displaystyle q} 792:{\displaystyle p} 746:{\displaystyle p} 724:dominant strategy 718:(if they reject). 440:Prob(Friend|Give) 359:Prob(Friend|Give) 321:choosing a value 271:For any value of 217:{\displaystyle p} 86: 85: 2854: 2816:Topological game 2811:No-win situation 2709:Thomas Schelling 2689:Robert B. Wilson 2649:Merrill M. Flood 2619:John von Neumann 2529:Ariel Rubinstein 2514:Albert W. Tucker 2365:War of attrition 2325:Matching pennies 2099:Pairing strategy 1961:Nash equilibrium 1884:Mechanism design 1849:Normal-form game 1804:Cooperative game 1777: 1770: 1763: 1754: 1753: 1747: 1743: 1712: 1703: 1696: 1690: 1689: 1687: 1685: 1679: 1670: 1664: 1663: 1661: 1659: 1653: 1644: 1577: 1575: 1574: 1569: 1567: 1566: 1546: 1544: 1543: 1538: 1536: 1535: 1527: 1517: 1515: 1514: 1509: 1507: 1506: 1498: 1484: 1482: 1481: 1476: 1474: 1473: 1465: 1455: 1453: 1452: 1447: 1445: 1444: 1436: 1423: 1421: 1420: 1415: 1413: 1412: 1404: 1398: 1397: 1381: 1379: 1378: 1373: 1371: 1370: 1362: 1349: 1347: 1346: 1341: 1339: 1338: 1330: 1324: 1323: 1307: 1305: 1304: 1299: 1297: 1296: 1288: 1274: 1272: 1271: 1266: 1264: 1263: 1255: 1246:). To calculate 1245: 1243: 1242: 1237: 1235: 1234: 1226: 1216: 1214: 1213: 1208: 1206: 1205: 1197: 1180: 1178: 1177: 1174:{\displaystyle } 1172: 1148: 1146: 1145: 1140: 1137: 1132: 1116: 1114: 1113: 1108: 1105: 1100: 1084: 1082: 1081: 1076: 1053:. The costs are 1052: 1050: 1049: 1044: 1042: 1041: 1025: 1023: 1022: 1017: 991:Public good game 955: 947:) or different. 941:multi-stage game 893: 891: 890: 885: 874:. Regardless of 873: 871: 870: 867:{\displaystyle } 865: 841: 839: 838: 833: 821: 819: 818: 813: 798: 796: 795: 790: 778: 776: 775: 770: 752: 750: 749: 744: 629:Pareto efficient 625: 623: 622: 617: 596: 594: 593: 588: 553: 551: 550: 545: 507: 505: 504: 499: 494: 466: 464: 463: 458: 437: 435: 434: 429: 349: 347: 346: 341: 293: 291: 290: 285: 249: 247: 246: 241: 223: 221: 220: 215: 28:Solution concept 19: 18: 2862: 2861: 2857: 2856: 2855: 2853: 2852: 2851: 2832: 2831: 2830: 2825: 2759: 2745:max^n algorithm 2718: 2714:William Vickrey 2674:Reinhard Selten 2629:Kenneth Binmore 2544:David K. Levine 2539:Daniel Kahneman 2506: 2500: 2476:Negamax theorem 2466:Minimax theorem 2444: 2405:Diner's dilemma 2260:All-pay auction 2226: 2212:Stochastic game 2164:Mean-field game 2135: 2128: 2094:Markov strategy 2030: 1896: 1888: 1859:Sequential game 1844:Information set 1829:Game complexity 1799:Congestion game 1787: 1781: 1751: 1750: 1740: 1716:Fudenberg, Drew 1713: 1706: 1697: 1693: 1683: 1681: 1677: 1673:Zack Grossman. 1671: 1667: 1657: 1655: 1651: 1645: 1641: 1636: 1627:signaling games 1609: 1593:English auction 1589: 1562: 1558: 1556: 1553: 1552: 1526: 1525: 1523: 1520: 1519: 1497: 1496: 1494: 1491: 1490: 1464: 1463: 1461: 1458: 1457: 1435: 1434: 1432: 1429: 1428: 1403: 1402: 1393: 1389: 1387: 1384: 1383: 1361: 1360: 1358: 1355: 1354: 1329: 1328: 1319: 1315: 1313: 1310: 1309: 1287: 1286: 1284: 1281: 1280: 1254: 1253: 1251: 1248: 1247: 1225: 1224: 1222: 1219: 1218: 1196: 1195: 1193: 1190: 1189: 1154: 1151: 1150: 1133: 1128: 1122: 1119: 1118: 1101: 1096: 1090: 1087: 1086: 1070: 1067: 1066: 1037: 1033: 1031: 1028: 1027: 1011: 1008: 1007: 953: 937: 925: 919:belief-system. 879: 876: 875: 847: 844: 843: 827: 824: 823: 807: 804: 803: 784: 781: 780: 758: 755: 754: 738: 735: 734: 701: 602: 599: 598: 573: 570: 569: 536: 533: 532: 490: 479: 476: 475: 446: 443: 442: 366: 363: 362: 326: 323: 322: 276: 273: 272: 229: 226: 225: 209: 206: 205: 198: 193: 141:sequential game 17: 12: 11: 5: 2860: 2850: 2849: 2844: 2827: 2826: 2824: 2823: 2818: 2813: 2808: 2803: 2798: 2793: 2788: 2783: 2778: 2773: 2767: 2765: 2761: 2760: 2758: 2757: 2752: 2747: 2742: 2737: 2732: 2726: 2724: 2720: 2719: 2717: 2716: 2711: 2706: 2701: 2696: 2691: 2686: 2681: 2679:Robert Axelrod 2676: 2671: 2666: 2661: 2656: 2654:Olga Bondareva 2651: 2646: 2644:Melvin Dresher 2641: 2636: 2634:Leonid Hurwicz 2631: 2626: 2621: 2616: 2611: 2606: 2601: 2596: 2591: 2586: 2581: 2576: 2571: 2569:Harold W. Kuhn 2566: 2561: 2559:Drew Fudenberg 2556: 2551: 2549:David M. Kreps 2546: 2541: 2536: 2534:Claude Shannon 2531: 2526: 2521: 2516: 2510: 2508: 2502: 2501: 2499: 2498: 2493: 2488: 2483: 2478: 2473: 2471:Nash's theorem 2468: 2463: 2458: 2452: 2450: 2446: 2445: 2443: 2442: 2437: 2432: 2427: 2422: 2417: 2412: 2407: 2402: 2397: 2392: 2387: 2382: 2377: 2372: 2367: 2362: 2357: 2352: 2347: 2342: 2337: 2332: 2330:Ultimatum game 2327: 2322: 2317: 2312: 2310:Dollar auction 2307: 2302: 2297: 2295:Centipede game 2292: 2287: 2282: 2277: 2272: 2267: 2262: 2257: 2252: 2250:Infinite chess 2247: 2242: 2236: 2234: 2228: 2227: 2225: 2224: 2219: 2217:Symmetric game 2214: 2209: 2204: 2202:Signaling game 2199: 2197:Screening game 2194: 2189: 2187:Potential game 2184: 2179: 2174: 2166: 2161: 2156: 2151: 2146: 2140: 2138: 2130: 2129: 2127: 2126: 2121: 2116: 2114:Mixed strategy 2111: 2106: 2101: 2096: 2091: 2086: 2081: 2076: 2071: 2066: 2061: 2056: 2051: 2046: 2040: 2038: 2032: 2031: 2029: 2028: 2023: 2018: 2013: 2008: 2003: 1998: 1993: 1991:Risk dominance 1988: 1983: 1978: 1973: 1968: 1963: 1958: 1953: 1948: 1943: 1938: 1933: 1928: 1923: 1918: 1913: 1908: 1902: 1900: 1890: 1889: 1887: 1886: 1881: 1876: 1871: 1866: 1861: 1856: 1851: 1846: 1841: 1836: 1834:Graphical game 1831: 1826: 1821: 1816: 1811: 1806: 1801: 1795: 1793: 1789: 1788: 1780: 1779: 1772: 1765: 1757: 1749: 1748: 1738: 1704: 1691: 1665: 1638: 1637: 1635: 1632: 1631: 1630: 1616: 1608: 1605: 1588: 1585: 1565: 1561: 1533: 1530: 1504: 1501: 1487: 1486: 1471: 1468: 1442: 1439: 1425: 1410: 1407: 1401: 1396: 1392: 1368: 1365: 1351: 1336: 1333: 1327: 1322: 1318: 1294: 1291: 1261: 1258: 1232: 1229: 1203: 1200: 1170: 1167: 1164: 1161: 1158: 1136: 1131: 1127: 1104: 1099: 1095: 1074: 1040: 1036: 1015: 994: 993: 987: 986: 983: 980: 976: 975: 972: 969: 965: 964: 961: 958: 952: 949: 945:repeated games 936: 933: 924: 921: 903: 902: 895: 883: 863: 860: 857: 854: 851: 831: 811: 800: 788: 768: 765: 762: 742: 720: 719: 708: 700: 697: 689: 688: 664: 615: 612: 609: 606: 586: 583: 580: 577: 555: 554: 543: 540: 513:Equilibrium 2. 497: 493: 489: 486: 483: 456: 453: 450: 427: 424: 421: 418: 415: 412: 409: 406: 403: 400: 397: 394: 391: 388: 385: 382: 379: 376: 373: 370: 351: 350: 339: 336: 333: 330: 303:Equilibrium 1. 283: 280: 269: 268: 267: 266: 263: 257: 254: 251: 239: 236: 233: 213: 197: 194: 192: 189: 185: 184: 170: 160: 159: 144: 84: 83: 81:signaling game 78: 74: 73: 71:Bayesian games 67: 63: 62: 59: 55: 54: 50: 49: 44: 40: 39: 35: 34: 24: 23: 15: 9: 6: 4: 3: 2: 2859: 2848: 2845: 2843: 2840: 2839: 2837: 2822: 2819: 2817: 2814: 2812: 2809: 2807: 2804: 2802: 2799: 2797: 2794: 2792: 2789: 2787: 2784: 2782: 2779: 2777: 2774: 2772: 2769: 2768: 2766: 2764:Miscellaneous 2762: 2756: 2753: 2751: 2748: 2746: 2743: 2741: 2738: 2736: 2733: 2731: 2728: 2727: 2725: 2721: 2715: 2712: 2710: 2707: 2705: 2702: 2700: 2699:Samuel Bowles 2697: 2695: 2694:Roger Myerson 2692: 2690: 2687: 2685: 2684:Robert Aumann 2682: 2680: 2677: 2675: 2672: 2670: 2667: 2665: 2662: 2660: 2657: 2655: 2652: 2650: 2647: 2645: 2642: 2640: 2639:Lloyd Shapley 2637: 2635: 2632: 2630: 2627: 2625: 2624:Kenneth Arrow 2622: 2620: 2617: 2615: 2612: 2610: 2607: 2605: 2604:John Harsanyi 2602: 2600: 2597: 2595: 2592: 2590: 2587: 2585: 2582: 2580: 2577: 2575: 2574:Herbert Simon 2572: 2570: 2567: 2565: 2562: 2560: 2557: 2555: 2552: 2550: 2547: 2545: 2542: 2540: 2537: 2535: 2532: 2530: 2527: 2525: 2522: 2520: 2517: 2515: 2512: 2511: 2509: 2503: 2497: 2494: 2492: 2489: 2487: 2484: 2482: 2479: 2477: 2474: 2472: 2469: 2467: 2464: 2462: 2459: 2457: 2454: 2453: 2451: 2447: 2441: 2438: 2436: 2433: 2431: 2428: 2426: 2423: 2421: 2418: 2416: 2413: 2411: 2408: 2406: 2403: 2401: 2398: 2396: 2393: 2391: 2388: 2386: 2383: 2381: 2378: 2376: 2375:Fair division 2373: 2371: 2368: 2366: 2363: 2361: 2358: 2356: 2353: 2351: 2350:Dictator game 2348: 2346: 2343: 2341: 2338: 2336: 2333: 2331: 2328: 2326: 2323: 2321: 2318: 2316: 2313: 2311: 2308: 2306: 2303: 2301: 2298: 2296: 2293: 2291: 2288: 2286: 2283: 2281: 2278: 2276: 2273: 2271: 2268: 2266: 2263: 2261: 2258: 2256: 2253: 2251: 2248: 2246: 2243: 2241: 2238: 2237: 2235: 2233: 2229: 2223: 2222:Zero-sum game 2220: 2218: 2215: 2213: 2210: 2208: 2205: 2203: 2200: 2198: 2195: 2193: 2192:Repeated game 2190: 2188: 2185: 2183: 2180: 2178: 2175: 2173: 2171: 2167: 2165: 2162: 2160: 2157: 2155: 2152: 2150: 2147: 2145: 2142: 2141: 2139: 2137: 2131: 2125: 2122: 2120: 2117: 2115: 2112: 2110: 2109:Pure strategy 2107: 2105: 2102: 2100: 2097: 2095: 2092: 2090: 2087: 2085: 2082: 2080: 2077: 2075: 2072: 2070: 2069:De-escalation 2067: 2065: 2062: 2060: 2057: 2055: 2052: 2050: 2047: 2045: 2042: 2041: 2039: 2037: 2033: 2027: 2024: 2022: 2019: 2017: 2014: 2012: 2011:Shapley value 2009: 2007: 2004: 2002: 1999: 1997: 1994: 1992: 1989: 1987: 1984: 1982: 1979: 1977: 1974: 1972: 1969: 1967: 1964: 1962: 1959: 1957: 1954: 1952: 1949: 1947: 1944: 1942: 1939: 1937: 1934: 1932: 1929: 1927: 1924: 1922: 1919: 1917: 1914: 1912: 1909: 1907: 1904: 1903: 1901: 1899: 1895: 1891: 1885: 1882: 1880: 1879:Succinct game 1877: 1875: 1872: 1870: 1867: 1865: 1862: 1860: 1857: 1855: 1852: 1850: 1847: 1845: 1842: 1840: 1837: 1835: 1832: 1830: 1827: 1825: 1822: 1820: 1817: 1815: 1812: 1810: 1807: 1805: 1802: 1800: 1797: 1796: 1794: 1790: 1786: 1778: 1773: 1771: 1766: 1764: 1759: 1758: 1755: 1746: 1745:Book preview. 1741: 1739:9780262061414 1735: 1731: 1727: 1726: 1721: 1717: 1711: 1709: 1701: 1695: 1676: 1669: 1650: 1643: 1639: 1628: 1624: 1620: 1617: 1614: 1611: 1610: 1604: 1602: 1598: 1594: 1584: 1581: 1563: 1559: 1550: 1528: 1499: 1466: 1437: 1426: 1405: 1399: 1394: 1390: 1363: 1352: 1331: 1325: 1320: 1316: 1289: 1278: 1277: 1276: 1256: 1227: 1198: 1186: 1182: 1165: 1162: 1159: 1134: 1129: 1125: 1102: 1097: 1093: 1072: 1062: 1060: 1059:Bayesian game 1056: 1038: 1034: 1013: 1005: 1001: 992: 988: 984: 981: 978: 977: 973: 970: 967: 966: 962: 959: 957: 956: 948: 946: 942: 932: 930: 923:More examples 920: 916: 913: 909: 900: 896: 881: 858: 855: 852: 829: 809: 801: 786: 766: 763: 760: 740: 732: 731: 730: 727: 725: 717: 713: 709: 706: 705: 704: 696: 694: 686: 682: 678: 673: 670:if a friend, 669: 665: 662: 658: 654: 649: 646:if a friend, 645: 641: 640: 639: 637: 632: 630: 613: 610: 607: 604: 584: 581: 578: 575: 566: 564: 560: 541: 538: 530: 526: 522: 518: 514: 511: 510: 509: 495: 491: 487: 484: 481: 472: 470: 454: 451: 448: 441: 425: 422: 419: 416: 413: 410: 404: 401: 392: 389: 386: 380: 374: 368: 360: 356: 337: 334: 331: 328: 320: 316: 312: 311:Do not accept 308: 304: 301: 300: 299: 297: 281: 278: 264: 261: 260: 258: 255: 252: 237: 234: 231: 211: 203: 202: 201: 188: 182: 178: 174: 171: 168: 165: 164: 163: 157: 153: 149: 145: 142: 138: 134: 133: 132: 130: 126: 121: 119: 115: 111: 107: 103: 102:dynamic games 99: 95: 91: 82: 79: 75: 72: 68: 64: 61:Cho and Kreps 60: 56: 51: 48: 45: 41: 36: 33: 29: 25: 20: 2669:Peyton Young 2664:Paul Milgrom 2579:HervĂ© Moulin 2519:Amos Tversky 2461:Folk theorem 2172:-player game 2169: 2089:Grim trigger 1970: 1724: 1720:Tirole, Jean 1694: 1682:. Retrieved 1668: 1656:. Retrieved 1647:James Peck. 1642: 1597:jump bidding 1590: 1587:Jump-bidding 1579: 1548: 1488: 1187: 1183: 1063: 1054: 997: 990: 938: 926: 917: 904: 898: 728: 721: 715: 711: 702: 692: 690: 684: 680: 676: 671: 667: 660: 656: 652: 647: 643: 633: 567: 562: 558: 556: 528: 524: 520: 516: 512: 473: 468: 439: 358: 354: 352: 318: 314: 310: 306: 302: 270: 199: 186: 180: 172: 166: 161: 155: 147: 136: 128: 124: 122: 93: 87: 53:Significance 38:Relationship 2786:Coopetition 2589:Jean Tirole 2584:John Conway 2564:Eric Maskin 2360:Blotto game 2345:Pirate game 2154:Global game 2124:Tit for tat 2054:Bid shading 2044:Appeasement 1894:Equilibrium 1874:Solved game 1809:Determinacy 1792:Definitions 1785:game theory 1725:Game Theory 1684:2 September 1004:public good 971:1-C1, 1-C2 699:Gift game 2 685:Do not give 668:Do not give 648:Do not give 196:Gift game 1 177:Bayes' rule 173:Consistency 90:game theory 58:Proposed by 32:game theory 2836:Categories 2430:Trust game 2415:Kuhn poker 2079:Escalation 2074:Deterrence 2064:Cheap talk 2036:Strategies 1854:Preference 1783:Topics of 1658:6 December 1634:References 125:strategies 2614:John Nash 2320:Stag hunt 2059:Collusion 1730:MIT Press 1564:∗ 1532:^ 1503:^ 1470:^ 1441:^ 1409:^ 1367:^ 1335:^ 1293:^ 1260:^ 1231:^ 1202:^ 1135:∗ 1103:∗ 764:− 579:≥ 485:≥ 449:≤ 420:− 402:− 390:− 332:≤ 235:− 43:Subset of 2755:Lazy SMP 2449:Theorems 2400:Deadlock 2255:Checkers 2136:of games 1898:concepts 1722:(1991). 1607:See also 982:1, 1-C2 974:1-C1, 1 912:subgames 822:, where 563:Not give 515:Sender: 307:Not give 305:Sender: 137:strategy 69:Dynamic 66:Used for 2507:figures 2290:Chicken 2144:Auction 2134:Classes 677:Reject. 521:Accept, 129:beliefs 77:Example 1736:  979:Don't 968:Build 963:Don't 960:Build 681:Reject 657:Accept 653:Accept 148:belief 2245:Chess 2232:Games 1678:(PDF) 1652:(PDF) 1551:than 1549:lower 156:types 104:with 1921:Core 1734:ISBN 1686:2016 1660:2021 1621:and 1580:less 1400:< 1326:> 985:0,0 672:Give 661:Give 644:Give 527:and 517:Give 355:Give 317:and 146:The 135:The 127:and 114:dove 110:hawk 92:, a 2505:Key 899:any 611:.99 474:If 88:In 30:in 2838:: 2240:Go 1732:. 1718:; 1707:^ 1603:. 1395:11 1321:00 1061:. 939:A 716:-1 693:no 582:.5 452:.5 335:.5 131:: 2170:n 1776:e 1769:t 1762:v 1742:. 1688:. 1662:. 1629:. 1560:c 1529:c 1500:c 1467:c 1438:c 1424:. 1406:c 1391:c 1364:c 1350:. 1332:c 1317:c 1290:c 1257:c 1228:c 1199:c 1169:] 1166:2 1163:, 1160:0 1157:[ 1130:i 1126:C 1098:i 1094:C 1073:i 1039:i 1035:C 1014:i 882:q 862:] 859:1 856:, 853:0 850:[ 830:q 810:q 787:p 767:p 761:1 741:p 712:0 614:, 608:= 605:p 585:. 576:p 542:. 539:x 496:2 492:/ 488:1 482:p 455:. 426:, 423:1 417:x 414:2 411:= 408:) 405:1 399:( 396:) 393:x 387:1 384:( 381:+ 378:) 375:1 372:( 369:x 338:. 329:x 282:, 279:p 238:p 232:1 212:p 143:.

Index

Solution concept
game theory
Bayesian Nash equilibrium
Bayesian games
signaling game
game theory
equilibrium concept
dynamic games
incomplete information
hawk
dove
Bayesian Nash equilibrium
sequential game
probability distribution
Bayes' rule
pooling equilibrium
Pareto efficient
separating equilibria
dominant strategy
subgame perfect Nash equilibrium
subgames
signaling game#Examples
multi-stage game
repeated games
free-rider problem
public good
Bayesian game
English auction
jump bidding
Jump bidding#signaling

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