清华大学博弈论3.pdf

序贯博弈 GGames withith SSequentitiall MovesMoves 第3章 ChapterChapter 33 内容提要内容提要 Outline 描述博弈：博弈树 Game trees 求解博弈：反转 Rollback 扩展扩展  增加参与者Adding more players 增加行动  增加行动 Adding more moves 证据证据 Evidedencesces Slide 2 序贯博弈 Sequential-move Games 序贯博弈要求一个有严格博弈顺序的策略环境。 SequentialSequential-movemove gamesgames entailentail strategicstrategic situations in which there is a strict order of pplayy. 参与者按顺序出招，并且知道在他们之前的那 些参与者都干了什么。 参与者都干了什么 Players take turns making their moves, and they know what players who have gone before them have done. Slide 3 序贯博弈 Sequential-move Games 无论何时采取行动，参与者都需要考虑他们当 前的行动会如何影响未来的行动，包括对手和 自己的行动 自己的行动。 Whenever actions are taken, players need to think about how their current need to think about how their current actions will influence future actions, both for their rivals and for themselves both for their rivals and for themselves. 参与者在计算未来后果的基础上，决定现在如 何出招何出招。。 Players thus decide their current moves on the basis of calculations of future consequences. Slide 4 博弈树 Game Trees 博弈树，或博弈的扩展型，是用来表示和分析 序贯博弈的图形方法序贯博弈的图形方法。。 A game tree, or the extensive form of a ggame is a ggrapphical techniqque for displaying and analyzing sequential- move games. 它表明了所有参与者能够采取的所有可能的行 动，指出了博弈的所有可能结果。 It illustrate all of the possible actions that can be taken by all of the players andand indicateindicate allall ofof thethe possiblepossible outcomes from the game. Slide 5 决策树与博弈树 Decision Trees vs. Game Trees