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以特徵向量法解條件分配相容性問題 / Solving compatibility issues of conditional distributions by eigenvector approach顧仲航, Ku, Chung Hang Unknown Date (has links)
給定兩個隨機變數的條件機率矩陣A和B,相容性問題的主要課題包
含:(一)如何判斷他們是否相容?若相容,則如何檢驗聯合分配的唯一性
或找出所有的聯合分配;(二)若不相容,則如何訂定測量不相容程度的方
法並找出最近似聯合分配。目前的文獻資料有幾種解決問題的途徑,例
如Arnold and Press (1989)的比值矩陣法、Song et al. (2010)的不可約
化對角塊狀矩陣法及Arnold et al. (2002)的數學規劃法等,經由這些方法
的啟發,本文發展出創新的特徵向量法來處理前述的相容性課題。
當A和B相容時,我們觀察到邊際分配分別是AB′和B′A對應特徵值1的
特徵向量。因此,在以邊際分配檢驗相容性時,特徵向量法僅需檢驗滿足
特徵向量條件的邊際分配,大幅度減少了檢驗的工作量。利用線性代數中
的Perron定理和不可約化對角塊狀矩陣的概念,特徵向量法可圓滿處理相
容性問題(一)的部份。
當A和B不相容時,特徵向量法也可衍生出一個測量不相容程度的簡單
方法。由於不同的測量方法可得到不同的最近似聯合分配,為了比較其優
劣,本文中提出了以條件分配的偏差加上邊際分配的偏差作為評量最近似
聯合分配的標準。特徵向量法除了可推導出最近似聯合分配的公式解外,
經過例子的驗證,在此評量標準下特徵向量法也獲得比其他測量法更佳的
最近似聯合分配。由是,特徵向量法也可用在處理相容性問題(二)的部份。
最後,將特徵向量法實際應用在兩人零和有限賽局問題上。作業研究的
解法是將雙方採取何種策略視為獨立,但是我們認為雙方可利用償付值表
所提供的資訊作為決策的依據,並將雙方的策略寫成兩個條件機率矩陣,
則賽局問題被轉換為相容性問題。我們可用廣義相容的概念對賽局的解進
行分析,並在各種測度下討論賽局的解及雙方的最佳策略。 / Given two conditional probability matrices A and B of two random
variables, the issues of the compatibility include: (a) how to determine
whether they are compatible? If compatible, how to check the uniqueness
of the joint distribution or find all possible joint distributions; (b)
if incompatible, how to measure how far they are from compatibility
and find the most nearly compatible joint distribution. There are
several approaches to solve these problems, such as the ratio matrix
method(Arnold and Press, 1989), the IBD matrix method(Song et
al., 2010) and the mathematical programming method(Arnold et al.,
2002). Inspired by these methods, the thesis develops the eigenvector
approach to deal with the compatibility issues.
When A and B are compatible, it is observed that the marginal distributions
are eigenvectors of AB′ and B′A corresponding to 1, respectively.
While checking compatibility by the marginal distributions, the
eigenvector approach only checks the marginal distributions which are
eigenvectors of AB′ and B′A. It significantly reduces the workload.
By using Perron theorem and the concept of the IBD matrix, the part
(a) of compatibility issues can be dealt with the eigenvector approach.
When A and B are incompatible, a simple way to measure the degree
of incompatibility can be derived from the eigenvector approach.
In order to compare the most nearly compatible joint distributions
given by different measures, the thesis proposes the deviation of the
conditional distributions plus the deviation of the marginal distributions
as the most nearly compatible joint distribution assessment standard.
The eigenvector approach not only derives formula for the most
nearly compatible distribution, but also provides better joint distribution
than those given by the other measures through the validations
under this standard. The part (b) of compatibility issues can also be
dealt with the eigenvector approach.
Finally, the eigenvector approach is used in solving game problems.
In operations research, strategies adopted by both players are assumed
to be independent. However, this independent assumption may not
be appropriate, since both players can make decisions through the
information provided by the payoffs for the game. Let strategies of
both players form two conditional probability matrices, then the game
problems can be converted into compatibility issues. We can use the
concept of generalized compatibility to analyze game solutions and
discuss the best strategies for both players in a variety of measurements.
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有限離散條件分配族相容性之研究 / A study on the compatibility of the family of finite discrete conditional distributions.李瑋珊, Li, Wei-Shan Unknown Date (has links)
中文摘要
有限離散條件分配相容性問題可依相容性檢驗、唯一性檢驗以及找出所有的聯合機率分配三層次來討論。目前的文獻資料有幾種研究方法,本文僅分析、比較其中的比值矩陣法和圖形法。
二維中,我們發現簡化二分圖的分支與IBD矩陣中的對角塊狀矩陣有密切的對應關係。在檢驗相容性時,圖形法只需檢驗簡化二分圖中的每個分支,正如同比值矩陣法只需檢驗IBD矩陣中的每一個對角塊狀矩陣即可。在檢驗唯一性時,圖形法只需檢驗簡化二分圖中的分支數是否唯一,正如同比值矩陣法只需檢驗IBD矩陣中的對角塊狀數是否唯一即可。在求所有的聯合機率分配時,運用比值矩陣法可推算出所有的聯合機率分配,但是圖形法則無法求出。
三維中,本文提出了修正比值矩陣法,將比值數組按照某種索引方式在平面上有規則地呈現,可降低所需處理矩陣的大小。此外,我們也發現修正比值矩陣中的橫直縱迴路和簡化二分圖中的迴路有對應的關係,因此可觀察出兩種方法所獲致某些結論的關聯性。在檢驗唯一性時,圖形法是檢驗簡化二分圖中的分支數是否唯一,而修正比值矩陣法是檢驗兩個修正比值矩陣是否分別有唯一的GROPE矩陣。修正比值矩陣法可推算出所有的聯合機率分配。
圖形法可用於任何維度中,修正比值矩陣法也可推廣到任何維度中,但在應用上,修正比值矩陣法比圖形法較為可行。 / The issue of the compatibility of finite discrete conditional distributions could be discussed hierarchically according to the compatibility, the uniqueness, and finding all possible joint probability distributions. There are several published methods, but only the Ratio Matrix Method and the Graphical Method are analyzed and compared in this thesis.
In bivariate case, a close correspondence between the components of the reduced bipartite graph and the diagonal block matrices of the IBD matrix can be found. When we examine the compatibility, just as simply each diagonal block matrix of the IBD matrix needs to be examined using the Ratio Matrix Method, so does each component of the reduced bipartite graph using the Graphical Method. When we examine the uniqueness, just as whether the number of the diagonal blocks of the IBD matrix is unique needs to be examined, so does the number of the components of the reduced bipartite graph. The Ratio Matrix Method can provide all possible joint probability distributions, but the Graphical Method cannot.
In trivariate case, this thesis proposes a Revised Ratio Matrix Method, in which we can present the ratio array regularly in the plane according to the index and reduce the corresponding matrix size. It is also found that each circuit in the revised ratio matrix corresponds to a circuit in the reduced bipartite graph. Therefore, the relation between the results of the two methods can be observed. When we examine the uniqueness with the Graphical Method, we examine whether the number of the components in the reduced bipartite graph is unique. But with the Revised Ratio Matrix Method, we examine whether each revised ratio matrix has a unique GROPE matrix. All possible joint probability distributions can be derived through the Revised Ratio Matrix Method.
The Graphical Method can be applied to the higher dimensional cases, so can the Revised Ratio Matrix Method. But the Revised Ratio Matrix Method is more feasible than the Graphical Method in application.
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