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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

BOT附屬事業放棄選擇權之研究-以台灣南北高速鐵路計畫為例

黃劉乾, Liu, Chang Huang Unknown Date (has links)
國內外對BOT實質選擇權之研究,大多集中於BOT主體本身所隱含之各種選擇權價值,鮮少論及BOT附屬事業之選擇權價值。惟因交通運輸BOT主體之自償率往往偏低,故須以保證最小運量或特許經營附屬事業等方式,來吸引潛在投資者。附屬事業對整個BOT計畫價值的影響頗大,如何針對其選擇權之價值加以分析為本研究的主要課題。個案將以台灣南北高速鐵路計畫為例,對其附屬事業之放棄選擇權加以探討。 本研究將主要探討下列課題,並提出研究結果: 一、有限差分法及蒙地卡羅模擬法計算選擇權價值,其間之差異?本 文利用有限差分法及蒙地卡羅模擬法來各別求算BOT 附屬事業的 放棄選擇權價值,一來了解 BOT 附屬事業的放棄選擇權價的大 小,二來比較有限差分法及蒙地卡羅模擬法兩者間的差異。 二、BOT附屬事業的放棄選擇權是否受主體事業的經營績效所影響? 三、BOT附屬事業是否須考量履約保證金之設計? 四、BOT主體決定經營或放棄時,是否會影響其附屬事業之放棄選擇 權價值? 本研究係以蒙地卡羅模擬法及有限差分法單獨估計台灣南北高速鐵路附屬事業之放棄選擇權價值,並建立運輸主體與附屬事業間價值的關聯,再以蒙地卡羅模擬法作更精確的估算。另使用單因子變異數分析及Tukey's Multiple Comparison Method之統計方法,驗證BOT主體與其附屬事業選擇權間之相關性,期能有助於日後BOT計畫之參與者評估及決策使用。 / The study of the Real Option Analysis (ROA) thesis of BOT generally focus is on the principal parts of the project only, rarely is considered the option of ancillary business of BOT. Because the self-liquidation-ratio of the transportation of BOT is low, it needs the government financial support (minimum traffic guarantee or revenue enhancements) to attract the interest of intended investors. The influence of the ancillary business of BOT is huge, so how to evaluate the option is the big issue of thesis. The case focus on the Taiwan High Speed Rail BOT project, and will study the option value of it’s ancillary business. Thesis will discuss the following issues, and develop the result of study. 1.The calculation difference between Monte Carlo Simulation & Finite Difference Method to work out option value, Thesis will use the Monte Carlo Simulation & Finite Difference Method to work out the abandon option value of ancillary business of BOT. To get the abandon option value and compare the calculation difference between Monte Carol Simulation & Finite Difference Method. 2.Will the abandon option value of ancillary business of BOT be influenced by the principal parts of the project? 3.Is there a need to consider the performance security deposit of ancillary business of BOT? 4.Will the decision of BOT impact the abandon option value of ancillary business or not? The thesis will use the Monte Carol Simulation & Finite Difference Method to calculate the abandon option value of ancillary business of Taiwan North-South High-Speed Railway Project (THR), and create the relation between the BOT & it’s ancillary business. The thesis will use the ANOVA & Tuley’s Multiple Comparison Method to validate the relationship, and hope it will let the participator to consider in the future.
82

模糊期望值與模糊變異數的檢定方法 / Methods on Testing Hypotheses of Fuzzy Mean and Fuzzy Variance

張曙光, Shu-Kuang,Chang Unknown Date (has links)
在許多實際情形下,傳統的統計檢定方法是不足以應付的。故本論文提出模糊檢定方法,我們定義出模糊樣本期望值與模糊樣本變異數的計算方法,再針對不同的模糊資料,分別提出不同的檢定方法,去解決最實際需要解決的問題,其中包括推廣古典的統計檢定方法與自創的檢定方法。 關鍵字:隸屬度函數,模糊樣本取樣,模糊樣本期望值,模糊樣本變異數,人性思考,t檢定,F檢定,模糊常態分配。 / In many expositions of fuzzy methods, fuzzy techniques are described as an alternative to a more traditional statistical approach. In this paper, we present a class of fuzzy statistical decision process in which testing hypothesis can be naturally reformulated in terms of interval-valued statistics. We provide the definitions of fuzzy mean, fuzzy distance as well as investigation of their related properties. We also give some empirical examples to illustrate the techniques and to analyze fuzzy data. Empirical studies show that fuzzy hypothesis testing with soft computing for interval data are more realistic and reasonable in the social science research. Finally certain comments are suggested for the further studies. We hope that this reformation will make the corresponding fuzzy techniques more acceptable to researchers whose only experience is in using traditional statistical methods. Key words: Membership function, fuzzy sampling survey, fuzzy mean, human thought, t-test, F-test, normally distributed.
83

亞洲金融市場整合與其對投資組合策略影響之研究—中國大陸之影響 / Asian Financial Market Integration and Its Effects on Portfolio Strategy— Mainland China's Impacts

黃聖仁, Huang, Sheng-Jen Unknown Date (has links)
本研究之宗旨在於探究中國大陸對亞洲區域內國家的金融市場影響程度之變化。由過去的各國股市日報酬率資料間相關程度與政策改變間的影響結果,來觀察是否未來在兩岸政策更開放下會使中國大陸對台灣的影響程度上升,進而使國際間投資組合的風險分散效果下降。本研究自DataStream選取台灣、香港、中國大陸、泰國、印尼、新加坡、馬來西亞、菲律賓、日本以及美國等十國的股價指數日資料,以對數轉換為日報酬率後年化加以分析。選取時間自1991年7月15日(中國大陸上海證券交易所股價指數公開後)至2008年12月31日。本研究選用的方法為使用風險值(VaR; Value at Risk)的概念來取代傳統的標準差,衡量以該十國所分別組成的各投資組合風險值變動情形;以及由風險值所衍生出的Diversification Benefit與Incremental VaR的結果。發現到僅由亞洲區域國家內組成的投資組合風險分散效果逐漸下降;且效果並不如有納入區域外國家(如美國)的投資組合。接著本研究將Gaussian Copula模型放入VaR中以增加對極端值的捕捉能力,結果發現本研究所選用的指數加權移動平均法所求得之相關係數已可有效反應出各國之間的相依程度,即加入Copula的效果有限。另外藉由Copula所求得之相關係數顯示,台灣、香港對中國大陸之間的相依程度已逐漸上升,並開始出現超越美國之現象,其中又以2005年為上升趨勢的起點。最後本研究以向量自我迴歸模型(VARs)來驗證2005年前後中國大陸股市對其他亞洲區域國家的影響力是否存在結構性的改變;並再佐以變異數拆解之方法來觀察2005年前後各國家之間自發性衝擊對彼此之間的影響程度變化。研究結果發現,透過VARs可證明中國大陸對亞洲區域各國的影響力在2005年後轉變為顯著;僅對美國不存在此一現象。另外變異數拆解的結果也顯示各國之間的相依程度在2005年後有明顯的上升,中國大陸對各國的影響程度亦然。透過本研究之結論,在未來兩岸將簽訂金融監理備忘錄使整合關係提升的環境下,需提醒投資人整合關係的上升將使得以之為標的之投資組合風險分散效果下降,需作為投資策略之考量。 / The object of this research is to find out the trend of dependence and correlation between China and other Asian countries. Based on past information about the relationship between equity markets’ correlation and changes in policies, this research can make suggestions to the foreseeable future of Taiwan and China whose relationship will be more solid due to new policy. The data of this research are gathered from DataStream, which includes Taiwan, Hong Kong, China, Thailand, Indonesia, Singapore, Malaysia, Philippines, Japan and United States. Selected from 1991/07/15 (when the Shanghai SE Composite went public) to 2008/12/31, this research calculates the annualized daily return using natural logarithms of two consecutive daily index prices. This research uses Value at Risk (VaR) to measure the risk exposure of portfolios formed by ten countries, and extends to the use of Diversification Benefit and Incremental VaR. The results found out that the diversification effects of portfolio which includes only Asian countries are decreasing and inferior to the effects when cross region countries are included. The second study of this research is to combine Gaussian Copula Model with VaR to capture the effects of extreme values. Empirical results found out that the VaR using Exponentially Weighted Moving Average method is good enough for analyzing Asian stock markets. The correlation in Copula model suggests that the dependence between Taiwan and China had increased since 2005 and has the increasing trend which might overwhelm the dependence between Taiwan and United States. Final research is about using Vector Autoregressions Model (VARs) to testify is there exist any structural change of dependence before and after 2005, and using Variance Decomposition to observe the relationships between these ten countries. The results found out that there exist structural change in 2005, the post-2005 periods shows that for Asian countries the effect from China are significant and greater than pre-2005 periods.
84

由消費者行為分析防偽標籤的市場需求 / Exploring the Demand of the Anti-Counterfeit Tag market -- From the perspective of Consumer Behavior

黃崇格, Huang, Chung-Ko Unknown Date (has links)
本研究有鑒於目前市場上仿冒品充斥,全球產業每年因偽造行為所產生的損失已高達美金4000億元左右,嚴重影響產業生存。為打擊仿冒現象,防偽產業因應而生,隨著消費者越來越重視消費權益及企業為了維護其品牌權益而蓬勃發展,嚴然已成為各種新產品不可或缺的附屬產品,防偽產業的未來發展及其競爭激烈是可以預期的。本論文提及的防偽標籤是專指『將單一或多種以上的防偽技術運用在可以黏貼或印製在目標產品的包裝或目標產品本身的標籤產品』。由於防偽標籤是附屬於目標產品,並非消費者所購買的標的。但透過對消費者購買行為的研究可以分析產品防偽的需求程度,進而提供產品製造商或供應商了解該產品是否需要防偽標籤?  本文首先蒐集消費者行為之文獻資料,找出消費者特性、消費者價值觀、消費者生活型態及消費者涉入程度等與防偽涉入程度相關的變數,整理各變數間的交互關係導出消費者對於防偽涉入程度會影響產品防偽的需求程度;其次透過焦點訪談及專家訪問內容得知,產品特性也是影響產品防偽的需求程度的重要因素;最後再由產品防偽的需求程度分析防偽標籤的市場需求。另一方面,不同的購買情境也會影響防偽標籤的市場需求,其中包括了購買通路以及標籤功效、法令規範、消費者對防偽標籤辨識能力等外在環境。 本研究經由消費者問卷調查,將所獲得的資料經由多變量變異數分析、相關分析及頻次分析等統計方法所得之結果來驗證假設。其結論均能滿足本研究所希望達到的五項目的。  一、影響防偽標籤市場需求的因素  二、影響消費者防偽涉入程度的因素  三、哪些特性的產品需要防偽標籤  四、哪些通路的產品需要防偽標籤  五、現階段防偽標籤的推廣成效 最後將本研究之發現作整理,提供防偽標籤業者作實務上的建議,希望這些參考意見在防偽產業擬定防偽標籤行銷策略時,能給予適切的助益。
85

台灣股票市場波動之研究 / The research of Taiwan's stock market volatility

陳功業, Chen, Kuang-Yeh Unknown Date (has links)
本文主要在探討影響台灣股票市場波動的因素,除了考慮以之前學者設定的 VAR(12)模型研究,另外以 SUR(5)模型來討論股市波動與基本面、交易面間的關係;最後,再以自我迴歸異質條件變異數模型來分析股市波動的特性。最重要的是,我們會根據誤差項的各類檢定結果來判定研究股市波動性質的最佳模型。 在聯立方程式的估計中,我們發現代表資訊到達指標的兩變數--週轉率與成交量成長率--會影響股票市場的波動。另外,我們找出交易面(成交量成長率)可能會影響基本面(匯率),這也就是說,在研究股市波動時,我們不需要特別區分變數的屬性。 在 GARCH 模型及 TGARCH 模型中,我們仍然可發現週轉率與成交量成長率會影響股市條件平均數或條件變異數;除此之外,好壞消息對股市日報酬率條件變異數(條件波動)應有不同的影響效果(壞消息的影響力較快反應)。而股市自身風險係數雖然統計檢定上不顯著異於零,但若未加入條件平均數的估計式,則可能會使模型得到較差的誤差項檢定結果,顯見股市自身風險應為影響投資人設定期望報酬率水準的重要因素之一。 從上述估計結果,我們可以知道,若散戶投資人能正確解讀市場上出現的各種新資訊之背後意義,將可使成交量成長率或週轉率(大部份可能代表無意義或不正確的交易行為)的變動幅度降低,進而有效地減少股票市場中股價異常波動的現象。 / My essay's topic focuses on discussing the factors that influence stock market volatility in Taiwan's stock market. Besides VAR(12) model as previous researchers have studied, I tries to set up SUR(5) models analyzing the relationship among the stock market volatility、the foundamental variables'volatilities and trading activities; Then I cited ARCH models ( autoregressive conditional heteroskedisticity models ) to find out the characteristics of stock market volatility. Most important of all, according to each misspecification test ( residual test ), I would specify the better models to describe the stock market volatility. In the estimations of system equations ( VAR(12)and SUR(5)models ), first I found that turnover rate and the growth rate of trading volume, which represent the information arrival indexes, could effect stock return's monthly conditional variance. Second, I especially found out the evidence that trading activities (trading volume growth) would probably have an impact on the macroeconomic variable ( exchange rate volatility ). It shows that we don't need to distinguish the attributes of those factors which could influence stock market volatility. In GARCH and TGARCH model, the positive influences of turnover and trading volume growth on daily stock return's conditional mean and conditional variance ( conditional volatility ) are still obvious, Within these TGARCH model, I discovered that bad news and good news could have different influences on stock market volatility ( the impact of bad news which resulted in downward movements of stock market volatility appeared faster that the good news'which caused upward movements). Stock market's self-risk(σ<sub>t-1</sub><sup>^2</sup>) is statistically insignificant different from zero in GARCH models, but when I omitted this variable in daily stock return's conditional mean estimation equation, standardized residual might not obey the assumption of normal distribution. It apparently told us that the stock market's self-risk term ( σ<sub>t-1</sub><sup>^2</sup> ) is one of the critical factors which influences investors to estimate expected return level. From those results above, we realized that if investors could precisely understand the real meanings of new information conveying in the stock market, it might decrease the levels of turnover and trading volume growth ( which could sometimes represent meaningless or inexact trading activities ), then effectively reduce the abnormal volatility phenomenon in stock market.
86

田口式品質工程方法在電子業應用之研究-華通電腦公司個案研究 / Application Of Taguchi's Quality Engineering Method In Electronic Industry--A Case Study of COMPEQ

張金生, Chang, Chin-Sheng Unknown Date (has links)
近年來,我國對於田口式品質工程方法的運用,已漸漸普及於各個生產事 業。然而,在以往田口方法的應用實例中大多只使用一種數據分析法,即 傳統實驗設計的變異數分析法,或田口方法的信號雜音比( S/N ratio ),對於二者之間的比較及異同處,則較少提及﹔且絕大部分是只探討單 一品質特性最佳化的問題,對於同一製程中同時具有多個品質特性需最佳 化的問題,亦較少觸及。本研究首先分別引用二種數據分析法進行提昇自 動光學檢驗(AOI)偵測能力」}的數據解析、比較二種分析法在理論上及應 用上的差別,並依保守原則,初步決定各品質特性(本研究有三個品質特 性)的最佳因子水準組合。其次,針對各品質特性間因子水準互相矛盾的 情形,本文將引用下述3種分析方法於研究案例,並綜合各種方法的優缺 點及適用狀況,藉以找出多品質特性同時最佳化的因子水準組合。此三種 分析方法為: (1) 畫出各因子對個別品質特性之影響效果總調查表,再經 由人為的比較判斷後選取最佳的條件組合 (2) 以個別品質特性之信號雜 音比的加權和作分析 (3) 使用品質特性值標準化的方法做分析由分析結 果,吾人可知現有各種方法均有其優缺點,唯有熟悉各種方法並配合豐富 經驗與專業知識,視實驗狀況而選擇性的加以應用,方能獲致良好實驗效 果。
87

外匯市場非線型時間序列之實證研究 --自迴歸條件異質變異數與類神經網路模式分析法 / A Non-linear Series Analysis of Foreign Market --An ARCH and Neural Approach

葉俊雄, Yeh, Jiunn Shyong Unknown Date (has links)
學界間廣泛地認為一般金融資產報酬具有的特性是:線型不可預測性,條件 異質變異數,非條件尖峰態 ... 等特性o 固然金融資產報酬具有線型不可 預測之特性,可是並不能否決其間可能有非線型依存關係的存在o目前大部 份經濟計量分析方法中的模式建構問題均是在假設模式的結構訊息已知的 條件下求解,然若真實體系的結構訊息未知或不明朗時,貿然地假設為某種 特定的模式結構,則可能又難於避免模式設定錯誤的困擾,因而對於真實體 系行為的描述亦將可能是誤導且不合理的,這意味著:除非該特定的模式結 構正是真實體系的表徵, 否則無論該特定模式的結構特性多完美,均難以 建構一令人信服的數理化模式來表徵真實體系之行為o 不幸地,此一問題 在高度非線型的動態隨機體系中尤其嚴重, 甚至是否存在一 ``真實'' 模式來據以表徵體系之行為,亦是相當值得懷疑, 故考慮一種無需特定結 構訊息假設的無母數方法或函數逼近法實屬必要o 類神經網路中的倒傳遞 網路模式即是符合此種特性的方法之一o然而學界間仍無法確定的是金融 資產報酬序列資料所產生的 ARCH 效果本身是否為真實序列資料產生機制 特性之顯現, 還是應歸咎於被忽略掉條件均數方面之非線性所衍生模式設 定錯誤情況下的代用模式, 並不得而知;另一方面, ARCH 模式的顯著成就 及其價值亦不能予以輕易地漠視, 因此, 試圖將 ARCH 模式所能提供的攸 關訊息納入倒傳遞網路模式的考量之中而形成倒傳遞網路-自迴歸條件異 質變異數 (BPN-ARCH) 模式以增進樣本外預測能力的精度便是本論文最 主要的嘗試重點與目的o
88

以厚尾分配及緩長記憶特性模型分析日圓匯率期貨報酬之風險值 / VaR Analysis for the Dollar/Yen Exchange Rate Futures Returns with Fat-Tails and Long Memory

鄭士緯, Cheng, Shih-Wei Unknown Date (has links)
本篇文章將採用長期記憶模型之一的HYGARCH模型,搭配1985年廣場協議後的日圓匯率期貨資料來估計日圓期貨匯率買入和放空部位的日報酬風險值,探討控管日圓匯率期貨在使用上的風險。為了更準確地計算風險值,本文採用常態分配、學生t分配以及偏態學生t分配來作模型估計以及風險值之計算。 本文實證的結果將有兩方面的貢獻:首先,實證結果顯示當我們採用厚尾分配估計風險值時,樣本內風險值的估計誤差會與信賴水準的高低呈正比的現象,證明在極端的風險值估計上,厚尾分配均有較佳的表現。其次,與其他使用HYGARCH模型研究日圓匯率的文章相較,本文在風險控管層面上所提供的偏態學生t分配,於估計風險值時,比起只考慮厚尾的對稱學生t分配將來得更為有效,其不但在估計誤差上較小,而且根據Kupiec檢定法,其在樣本內的風險值估計也有較好的表現。此外,本文也將多方證明此資料的偏態分配屬於右偏。 / In order to manage the exposure of the dollar/yen futures returns with regarding the long memory behavior in volatility, we use the HYGARCH(1,d,1) model with the data after the Plaza Accord to compute daily Value-at-Risk (VaR) of long and short trading positions. To take into account the fat-tail situation in financial time series, we estimate the model under the normal, Student-t, and skewed Student-t distributions. The contribution of this article is twofold. First, the empirical results show that the bias of in-sample VaR increases as the confidence level increases when VaR is calculated with a fat-tail distribution. Second, we provide a better distribution, the skewed Student-t innovation, for estimating the HYGARCH model for the Japanese yen in respect of risk management because the bias under the skewed Student-t innovation is smaller than that under the Student-t distribution, and in-sample VaR of the models with a skewed Student-t distribution outperforms based on Kupiec test. In addition, we get the innovation skewed to the right through the in-sample VaR analysis.
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準蒙地卡羅法於多資產路徑相依債券之評價

張極鑫, Chang, Chi-Shin Unknown Date (has links)
近年來隨著法規與市場逐漸的開放,使得券商可以發行衍生性商品的種類也逐漸增加,而在眾多結構型商品中,不少商品其連結標的包含了多資產與路徑相依條款,可以看成投資一藍子股票且具有多個觀察時間的商品,一方面若連結資產上漲投資人將可得到一定的報酬,另外一方面同時具有下方保護的條款可避免本金嚴重虧損。 而此類商品包含了多資產連結且有路徑相依條款,在評價方面是一個高維度的問題,若使用傳統的蒙地卡羅法來評價,因其收斂速度緩慢常需秏費大量的計算時間,使得蒙地卡羅法在應用上有此缺點,一般來說可以使用對立變數法或控制變數法來改進收斂的速度,另外也可以使用低差異性數列即所謂的準蒙地卡羅法來改進收斂速度,並且準蒙地卡羅法與布朗橋結構或主成份分析法相結合還可加快收斂速度。 本文主要提供二種不同報酬型態的商品,第一個商品為低維度上入局商品,其報酬型態與障礙型選擇類似,第二個商品為連結多資產且路徑相依商品,以此兩商品來探討各種不同方法在不同報酬型態下的收斂速度與準確性,最後文中模擬的結果顯示在所有方法中,使用準蒙地卡羅法結合主成份分析法皆可以得到不錯的收斂速度與準確性。
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評估極值相依組合信用風險之有效演算法 / Efficient Algorithms for Evaluating Portfolio Credit Risk with Extremal Dependence

施明儒, Shih,Ming Ju Unknown Date (has links)
蒙地卡羅模擬是在組合信用風險的管理上相當實用的計算工具。衡量組合信用風險時,必須以適當的模型描述資產間的相依性。常態關聯結構是目前最廣為使用的模型,但實證研究認為 t 關聯結構更適合用於配適金融市場的資料。在本文中,我們採用 Bassamboo et al. (2008) 提出的極值相依模型建立 t 關聯結構用以捕捉資產之間的相關性。同時,為增進蒙地卡羅法之收斂速度,我們以 Chiang et al. (2007) 的重要性取樣法為基礎,將其拓展到極值相依模型下,並提出兩階段的重要性取樣技巧確保使用此方法估計一籃子信用違約時,所有模擬路徑均會發生信用事件。數值結果顯示,所提出的演算法皆達變異數縮減。而在模型自由度較低或是資產池較大的情況下,兩階段的重要性取樣法將會有更佳的估計效率。我們也以同樣的思路,提出用以估計投資組合損失機率的演算法。雖然所提出的演算法經過重要性取樣的技巧後仍無法使得欲估計的事件在所有模擬路徑下都會發生,但數值結果仍顯示所提出的方法估計效率遠遠優於傳統蒙地卡羅法。 / Monte Carlo simulation is a useful tool on portfolio credit risk management. When measuring portfolio credit risk, one should choose an appropriate model to characterize the dependence among all assets. Normal copula is the most widely used mechanism to capture this dependence structure, however, some emperical studies suggest that $t$-copula provides a better fit to market data than normal copula does. In this article, we use extremal depence model proposed by Bassamboo et al. (2008) to construct $t$-copula. We also extend the importance sampling (IS) procedure proposed by Chiang et al. (2007) to evaluate basket credit default swaps (BDS) with extremal dependence and introduce a two-step IS algorithm which ensures credit events always take place for every simulation path. Numerical results show that the proposed methods achieve variance reduction. If the model has lower degree of freedom, or the portfolio size is larger, the two-step IS method is more efficient. Following the same idea, we also propose algorithms to estimate the probability of portfolio losses. Althought the desired events may not occur for some simulations, even if the IS technique is applied, numerical results still show that the proposed method is much better than crude Monte Carlo.

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