徐東方
(河南職業(yè)技術(shù)學(xué)院基礎(chǔ)部 河南鄭州 450046)
徐東方
(河南職業(yè)技術(shù)學(xué)院基礎(chǔ)部 河南鄭州 450046)
對(duì)策的限制是指局中人集合上每一個(gè)模糊結(jié)盟到其子對(duì)策的單調(diào)映射,實(shí)際上這種限制對(duì)策考慮的是參與合作的局中人在模糊結(jié)盟中受到某種限制的情形。本文在文獻(xiàn)[1,2]基礎(chǔ)上定義了t?限制對(duì)策的核心,同時(shí)給出t?限制對(duì)策的公理化特征,并舉例說明限制對(duì)策與常規(guī)結(jié)盟對(duì)策的聯(lián)系及一致性。
t?限制對(duì)策;合作對(duì)策;模糊結(jié)盟;核心
在合作對(duì)策的經(jīng)典模型中,局中人集合的每一個(gè)子集認(rèn)為是按照自己權(quán)力隨意組成的聯(lián)盟,模糊結(jié)盟對(duì)策可以看成是建立在局中人參與率上的實(shí)值函數(shù),但是在現(xiàn)實(shí)生活中我們知道結(jié)盟中的每一個(gè)局中人為了自己的利益可以拒絕參加某一個(gè)結(jié)盟,可以任意選擇對(duì)某一結(jié)盟的參與程度(即參與率),有時(shí)局中人對(duì)某一個(gè)結(jié)盟的參與受到一定外界條件的限制,這說明經(jīng)典合作對(duì)策模型中的一些結(jié)盟是不存在的。結(jié)盟受到約束的合作對(duì)策更貼近于現(xiàn)實(shí)中對(duì)策模型,因此對(duì)其研究十分必要。許多學(xué)者從不同角度提出了結(jié)盟的限制形式,并在限制的結(jié)盟集上討論分配問題,如張盛開提出的隨機(jī)結(jié)盟對(duì)策,[3]U Faigle和W Kern的有優(yōu)先約束的對(duì)策,[4]G Owen的圖限制對(duì)策[5]等,本文的t?限制對(duì)策是對(duì)局中人在某一結(jié)盟參與率進(jìn)行約束的一種情形。實(shí)際上研究t?限制對(duì)策就是在其子結(jié)盟構(gòu)成的集族上研究相應(yīng)對(duì)策及其分配問題,本文討論t?限制對(duì)策的核心,并給出t?限制對(duì)策核心的公理化特征。
現(xiàn)在定義限制對(duì)策的另外兩種核心:
證明:
此性質(zhì)被稱為平均遞增邊緣收益性(IAMR)。
由引理1,引理2同理可證vt滿足定義4的超模性和單坐標(biāo)凸性,由此可證vt亦滿足IAMR性,即此時(shí)vt為凸對(duì)策。即證。
t1則相應(yīng)地,
相對(duì)應(yīng)的分配集為:
由此可以看出t?限制對(duì)策的分配集和核心是其對(duì)應(yīng)模糊對(duì)策分配集和核心的子集。
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Cores for Fuzzy coalition Game with t?restriction
A “restriction”is a monotonic map assigning to each fuzzy coalition of a finite player set a sub?coalitionIn fact,this kind of t?restricted games consider those cooperation participate rate among players is constrained. The paper define the cores for t?restricted game based on reference[1,2]and the axioms that characterize t ? restricted game are proposed. An example is given to illustrate the relation and consistency between t?restricted game and normal fuzzy cooperative games.
t?restricted game; cooperative games; fuzzy coalition; core
徐東方(1981-),男,河南周口市人,河南職業(yè)技術(shù)學(xué)院教師,助教,理學(xué)碩士,主要研究方向:應(yīng)用數(shù)學(xué);運(yùn)籌學(xué);對(duì)策論。
2010-05-11