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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

隨機利率下之資產交換-跨通貨股酬交換與利率交換的評價與避險 / Asset Swap Under Stochastic Interest Rate__The Pricing and Hedging of Cross-Currency Equity Swap and Interest Rate Swap

姜碧嘉, Chiang, Bi-Chia Unknown Date (has links)
雖然跨通貨股酬交換在國際投資市場扮演著重要的角色,但文獻上關於股酬交換評價模式的相關探討並不多,且多集中於國內市場或以本國貨幣做為支付幣別的股酬交換。對於跨通貨股酬交換而言,其評價模式較國內股酬交換之評價模式複雜許多,如何將影響其價值之股價指數、匯率與利率此三個主要因子間的交互相關性同時加入考量,即是此產品之評價過程的重點。 本文在完全市場的假設下,同時放寬傳統評價方法之各變數之相關係數為固定值的假設,提出一新的股酬交換評價方法,即以『兩階段兩步驟』之較具經濟含意的複製方式,推導出股酬交換的一般化評價公式。透過此複製方法,可更清楚得知股酬交換於存續期間的價值變動,更可進一步求得其避險方式,以提供股酬交換交易商在面臨不對稱風險(mismatch risk)時的避險方法。而本文的第二個貢獻在於,將本文所提出之『兩階段兩步驟』的複製方法應用於利率交換的評價上,推導出跨通貨利率交換的一般化評價模式,以進一步比較股酬交換與利率交換此兩種商品的差異性,並試圖釐清市場上對於跨通貨股酬交換評價上的誤解。 與傳統評價公式最大的差異在於:本文評價公式額外考慮了一修正項,複製投資組合可藉由此修正項,對未來各參數間的變動隨時做出調整,以使投資組合能完全複製跨通貨股酬交換的價值。 本文發現,對於國內投資人支付固定利率,以交換B市場的股價指數報酬,且以C國的貨幣做為支付幣別的跨通貨股酬交換而言,其價值除了受到當期利率期間結構的影響外,在期初或每期交換後,其價值與股價指數無直接關聯,但在兩支付間,其價值則會受到當時股價指數與前期股價指數之相對比例的影響。同時,C國對本國的未來匯率並未直接影響跨通貨股酬交換的價值。且若假設各國遠期利率的波動度為零下,則當B國股價指數與C國對本國的匯率呈現正關係或當B國股價指數與B國對本國的匯率呈現負關係時,跨通貨股酬交換的價值愈大。另外,市場上投資人通常誤認股酬交換的價值等於利率交換價值,對於股酬交換與利率交換的比較,本文發現在大多數的情況下,股酬交換的價值與利率交換的價值並不相等。
82

獎勵與懲罰對租稅逃漏與規避行為之影響 / The Effect of Reward-Penalty System on Tax Aversion

呂欣茹, Lu, Hsin Ju Unknown Date (has links)
現行有關逃漏稅研究的國內外文獻,無論在理論推導或實證分析上,多集 中於非法的租稅逃漏(tax evasion)上,而忽略了另一種合法的減少稅 負的方法:租稅規避(tax avoidance)。本文乃將 Falkinger & Walther (1991) 獎懲並行的制度與傳統的租稅逃避(tax aversion)理 論相結合,而以較嚴謹的方式分析聯合的個人租稅逃漏與租稅規避的選擇 行為,即所謂的租稅逃避行為。本文共分為四章十節,略述如下:第一章 為緒論,分為三節,分別說明研究動機與目的、研究範圍與方法及章節安 排。第二章為文獻回顧,分為三節,以國、內外文獻為探討單元,分別依 時間順序及研究範圍與方法,針對租稅逃漏、租稅規避與租稅逃避聯合決 策行為等三個領域的文獻作假設分析與結論整理,最後則做一小結。第三 章為獎懲並行的租稅逃避理論( A Mixed Penalty- Reward Tax Aversion Theory ),分為三節,第一節介紹獎懲並行的租稅逃避理論, 主要分成基本假設、模型設立、比較靜態分析和加入獎勵因素後的影響四 部份來討論。第二節乃以獎懲並行的租稅逃避模型與前章中所述較具代表 性的逃、避稅理論模型加以比較。最後則作一小結。第四章為結論,僅一 節。由於另一租稅減少途徑──租稅規避──的存在改變了許多僅討論租 稅逃漏文獻的結論。本文主要的結論是,除了查獲率和邊際懲罰率的變動 對申報所得和避稅所得佔總逃避所得的份額有明確的正向影響外,其他相 關變數如總所得、邊際稅率和邊際避稅成本的變動所造成的影響均不明確 ;而邊際獎勵率的變動對申報所得的影響亦無法確定,然其對避稅所得佔 總逃避稅所得的份額卻造成(反直觀的)負面的效果。此外,提高獎勵率 是否提高或降低其他變數變動的效果,其答案亦無法肯定。這些發現表 示 Falkinger & Walther (1991) 對於採用獎勵制度的優點似乎有誇大之 嫌。
83

二次擔保債權憑證之評價及其風險衡量-條件機率獨立模型 / The Valuation and Risk Measure of CDO-Squared under Conditional Independence

陳嘉祺 Unknown Date (has links)
本文的主旨在評價二次擔保債權憑證。在條件獨立機率的假設下,我們使用factor copula的方法去刻劃違約事件間的相關係數,並提供了一個有效率的迴圈演算法去建構損失分配。本方法同時考慮違約數目及違約位置,同時亦可解決重疊性的問題。本文所建構的是Hull and White(2004)的延申模型。我們也對各參數作敏感度分析,以求得其對分券價差的影響。文中亦主張一些風險衝量指標,以量化重疊性的程度等風險議題。 / In this paper we address the pricing issues of CDO of CDOs. Underlying the conditional indepdence assumption we use the factor copula approach to characterize the correlation of defaults events. We provide an efficient recursive algorithm that constructs the loss distribution. Our algorithm accounts for the number of defaults, the location of defaults among inner CDOs, and in addition the degree of overlapping between inner CDOs. Our algorithm is a natural extension of the probability bucketing method of Hull and White (2004). We analyze the sensitivity of different parameters on the tranche spreads of a CDO-squared, and in order to characterize the risk-reward profiles of CDO-squared tranches, we introduces appropriate risk measures that quantify the degree of overlapping among the inner CDOs. Hull and White (2004) presents a recursive scheme known as probability bucketing approach to construct conditional loss distribution of CDO. However, this approach is insufficient to capture the complexities of CDO². In the case of the modeling of CDO, we are concerned for the probabilities of different number of defaults upon a time horizon t, e.g., the probabilities of 3 defaults happened within a year. With the mentioned probabilities, we can then calculate the expected loss within the time horizon, which enables us to figure out the spreads of CDO. However, in the modeling of CDO², an appropriate valuation should be able to overcome two more difficulties: (1) the overlapping structure of the underlying CDOs, and (2) the location where defaults happened, in order to get the fair spreads of CDO².
84

相依競爭風險邊際分配估計之探討

張簡嘉詠 Unknown Date (has links)
競爭風險之下對邊際分配的估計,是許多領域中常遇到的問題。由於主要事件及次要事件互相競爭,只要一種事件先發生即終止對另一事件的觀察,在兩事件同時發生的機率為0之下,連一筆完整的資料我們都無法蒐集到。除非兩事件互為獨立或加上其它條件,否則會有邊際分配無法識別的問題。但是獨立的條件在有些情況下並不合理,為解決相依競爭風險之邊際分配無法識別的問題,可先假定兩事件發生時間之間的關係。 由於關聯結構定義出兩變數間的結合關係,我們可利用關聯結構解釋兩事件發生時間之間的關係。假定兩變數之相關性參數為已知,且採用機率積分轉換的觀念,本論文討論了Zheng 與 Klein提出的關聯結構-圖形估計量,是否會依設限程度、相關性強度和關聯結構形式的不同,以致估計能力有別。 / The problem of estimating marginal distributions in a competing risks study is often met in scientific fields. Because main event and secondary event compete with each other, and a first occurring event prevents us from observing another event promptly, the intact lifetimes or survival times are unable to be collected in the circumstances that the probability of both lifetimes coinciding is 0. Unless lifetimes being independent or adding other conditions, there is a problem that the marginal distributions are non-identifiable. But the condition of independence is not always reasonable, we may assume the relation between lifetimes has some special form Because the copula defines the association between two variables, it can be employed to explain relation between lifetimes. Assuming that the dependence parameter in the copula framework is known, and adopting the concept of the probability integral transformations, this thesis has demonstrated whether the estimating abilities of the copula-graphic estimator, that Zheng and Klein put forward, are different in rates of censoring, intensities of dependence, and forms of the copula.
85

離散條件機率分配之相容性研究 / On compatibility of discrete conditional distributions

陳世傑, Chen, Shih Chieh Unknown Date (has links)
設二個隨機變數X1 和X2,所可能的發生值分別為{1,…,I}和{1,…,J}。條件機率分配模型為二個I × J 的矩陣A 和B,分別代表在X2 給定的條件下X1的條件機率分配和在X1 給定的條件下X2的條件機率分配。若存在一個聯合機率分配,而且它的二個條件機率分配剛好就是A 和B,則稱A和B相容。我們透過圖形表示法,提出新的二個離散條件機率分配會相容的充分必要條件。另外,我們證明,二個相容的條件機率分配會有唯一的聯合機率分配的充分必要條件為:所對應的圖形是相連的。我們也討論馬可夫鏈與相容性的關係。 / For two discrete random variables X1 and X2 taking values in {1,…,I} and {1,…,J}, respectively, a putative conditional model for the joint distribution of X1 and X2 consists of two I × J matrices representing the conditional distributions of X1 given X2 and of X2 given X1. We say that two conditional distributions (matrices) A and B are compatible if there exists a joint distribution of X1 and X2 whose two conditional distributions are exactly A and B. We present new versions of necessary and sufficient conditions for compatibility of discrete conditional distributions via a graphical representation. Moreover, we show that there is a unique joint distribution for two given compatible conditional distributions if and only if the corresponding graph is connected. Markov chain characterizations are also presented.
86

由市場的選擇權價格還原風險中立機率分布

張瓊方, Chang, Chiung-Fang Unknown Date (has links)
本論文提出線性規劃的方法以還原隱藏於選擇權市場價格中的風險中立機率測度,並利用該機率測度計算選擇權的合理價格。模型中假設選擇權對應同一標的資產與到期日,資產價格於到期日的狀態為離散點且個數有限,當市場不具任何套利機會時,以極小化市場價格與合理價格之離差總和作為挑選風險中立機率測度的準則。最後,以臺指選擇權(TXO)的交易資料做為實證對象。實證中發現,加入平滑限制式與離差權重之線性規劃模型在評價歐式選擇權合理價格的效能最為優異。 / The thesis proposes a liner programming to recover the risk-neutral probability distribution of an underlying asset price from its associated market option prices, and we evaluate the fair prices of options via the resulting risk-neutral probability distribution. Assume that we face a series of European options with different exercise prices on the same maturity and underlying asset in this linear programming model. The criterion of choosing a risk-neutral probability distribution is minimizing the sum of total deviations subject to requiring that the fair prices of options are consistent with observed market option prices. Finally, we take the trading data of TXO as an empirical study. The empirical study indicates that the model with smooth constraints and weighted deviations has the best performance in pricing the rational price of European options.
87

信用違約機率之預測─Robust Logitstic Regression

林公韻, Lin,Kung-yun Unknown Date (has links)
本研究所使用違約機率(Probability of Default, 以下簡稱PD)的預測方法為Robust Logistic Regression(穩健羅吉斯迴歸),本研究發展且應用這個方法是基於下列兩個觀察:1. 極端值常常出現在橫剖面資料,而且對於實證結果往往有很大地影響,因而極端值必須要被謹慎處理。2. 當使用Logit Model(羅吉斯模型)估計違約率時,卻忽略極端值。試圖不讓資料中的極端值對估計結果產生重大的影響,進而提升預測的準確性,是本研究使用Logit Model並混合Robust Regression(穩健迴歸)的目的所在,而本研究是第一篇使用Robust Logistic Regression來進行PD預測的研究。 變數的選取上,本研究使用Z-SCORE模型中的變數,此外,在考慮公司的營收品質之下,亦針對公司的應收帳款週轉率而對相關變數做了調整。 本研究使用了一些信用風險模型效力驗證的方法來比較模型預測效力的優劣,本研究的實證結果為:針對樣本內資料,使用Robust Logistic Regression對於整個模型的預測效力的確有提升的效果;當營收品質成為模型變數的考量因素後,能讓模型有較高的預測效力。最後,本研究亦提出了一些重要的未來研究建議,以供後續的研究作為參考。 / The method implemented in PD calculation in this study is “Robust Logistic Regression”. We implement this method based on two reasons: 1. In panel data, outliers usually exist and they may seriously influence the empirical results. 2. In Logistic Model, outliers are not taken into consideration. The main purpose of implementing “Robust Logistic Regression” in this study is: eliminate the effects caused by the outliers in the data and improve the predictive ability. This study is the first study to implement “Robust Logistic Regression” in PD calculation. The same variables as those in Z-SCORE model are selected in this study. Furthermore, the quality of the revenue in a company is also considered. Therefore, we adjust the related variables with the company’s accounts receivable turnover ratio. Some validation methodologies for default risk models are used in this study. The empirical results of this study show that: In accordance with the in-sample data, implementing “Robust Logistic Regression” in PD calculation indeed improves the predictive ability. Besides, using the adjusted variables can also improve the predictive ability. In the end of this study, some important suggestions are given for the subsequent studies.
88

促進中小企業創新之智慧型激勵故事生成 / Towards motive driven story generation for encouraging SMEs Innovation

邱芃瑋, Chiu, Peng Wei Unknown Date (has links)
面臨到現今社會的激烈競爭,服務創新是應付此環境變化的趨勢之一,但大部分台灣的中小企業主並不知道如何將服務創新實踐在他們的企業中。另一方面,大部分中小企業主並不清楚什麼是服務創新,即使知道服務創新可以改善他們的事業,也缺乏實踐的勇氣。因此,為了改善以上的情況,本篇論文的主旨是引用動機理論來建構小客製化的小故事廣告來激勵中小企業主,並讓他們明白服務創新的好處且有勇氣去實踐。為了達到這個目標,我們使用機率擴展有限狀態機(Probabilistic Extended FSM)作為實踐的方法,利用Dramatica的故事元素和十種創新類型的元素並以三幕劇來建構故事架構,在整合中小企業主的相關資料形成完整的激勵故事。從該激勵故事中,中小企業主可以得到一些啟示,改善岌岌可危的業務以實現他們心中的理想。 / Service innovation is one of the tendencies to cope with the environmental change in the current fierce competition, but the most SMEs in Taiwan don’t know how to put service innovation into practice in their business. On the other hand, the most SMEs don’t know what service innovation is; however, even they know service innovation could rescue their poor business; they have no courage to do so. For these reasons which mentioned above, the aim of this research is to reference the motivation theory and try to generate the mini customized advertising-like to stimulate SMEs and let them know the advantage of service innovation and have confidence to do so. In order to achieve this goal, we use Probabilistic Extended FSM as the implementation approach to integrate the private information of our target SMEs with the story framework which is constituted by the three-act Structure including the Dramatica elements and the elements of ten types of innovation. By this kind of stimulating mini customized advertising-like story, the SMEs could get some enlightenment to ameliorate the precarious business to achieve the ideal of their mind.
89

漲跌停板限制下之股票報酬機率分配

葉宜欣, Yeh, Yi-Shian Unknown Date (has links)
股票市場的報酬率相對於金融市埸是非常重要的,因為其背後的真實機率分配對各種資產定價及選擇權的評價模型都有決定性的影響。本文考慮台灣股票市埸具有漲跌停板的限制來驗證實證中股票報酬機率分配的「厚尾」的現象,希望透過我們的研究能對財務理論在國內金融市埸的應用有更進一步的了解。我們選定了常態分配、對數常態分配及一般化第二種貝它分配 (GB2)來當作是台灣股票報酬率的真實機率分配,以動差法比較再以概似比檢定法(LR test)選出一表現最好的機率分配。由選取的25支國內股票中發現一般化第二種貝它分配 (GB2)可以解釋偏態和峰態對報酬率的影響並且也是概似比檢定法所選出的最適報酬率分配,由此可知一般化第二種貝它分配 (GB2)較為適合作為台灣股票報酬的真實機率分配。
90

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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