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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.
51

Multifractal Analysis for the Stock Index Futures Returns with Wavelet Transform Modulus Maxima / 股價指數期貨報酬率的多重碎形分析與小波轉換的模數最大值

洪榕壕, Hung,Jung-Hao Unknown Date (has links)
本文應用資產報酬率的多重碎形模型,該模型為一整合財務時間序列上的厚尾及波動持續性的連續時間過程。多重碎形的方法允許我們估計隨時間變動的報酬率高階動差,進而推論財務時間序列的產生機制。我們利用小波轉換的模數最大值計算多重碎形譜,透過譜分解得到資產報率分配的高階動差資訊。根據實證結果,我們得到S&P和DJIA的股價指數期貨報酬率符合動差尺度行為且資料也展現幕律的形態。根據估計出的譜形態為對數常態分配。實證結果也顯示S&P和DJIA的股價指數期貨報酬率均具有長記憶及多重碎形的特性。 / We apply the multifractal model of asset returns (MMAR), a class of continuous-time processes that incorporate the thick tails and volatility persistence of financial time series. The multifractal approach allows for higher moments of returns that may vary with the time horizon and leads to infer about the generating mechanism of the financial time series. The multifractal spectrum is calculated by the Wavelet Transform Modulus Maxima (WTMM) provides information on the higher moments of the distribution of asset returns and the multiplicative cascade of volatilities. We obtain the evidences of multifractality in the moment-scaling behavior of S&P and DJIA stock index futures returns and the moments of the data represent a power law. According to the shape of the estimated spectrum we infer a log normal distribution.The empirical evidences show that both of them have long memory and multifractal property.
52

團隊式任務發掘於多重代理人系統 / Team-Based Mission Discovery in Multi-Agent Systems

林宜謙, LIN, I-Chien Unknown Date (has links)
過去多重代理人系統相關研究中,皆假設任務是預先知道而且確定的,這使得它們無法即時滿足使用者需求,因而在實務上受到限制。因此本研究期望能將多重代理人系統的工作向前延伸,引入人類社會中的價值觀,進而模擬出人類解決問題的思考模式,將能夠放寬任務給定的限制,幫助傳統多重代理人系統提昇彈性、適用於更為動態複雜的環境,即時地滿足使用者需求。任務發掘意指幫助多重代理人系統找出合適任務的過程,將任務發掘應用於多重代理人系統,最主要的挑戰在於-「什麼任務才能滿足需求」;換句話說,「找出需求」。價值(value)正是引起社會交換(social exchange)的元素,價值觀則是人類對於該價值之看法。重視該價值觀為希望於交換過程中獲得該價值,不重視該價值觀為願意於交換過程中犠牲該價值,然而重視有程度之分,即希望獲得/願意犠牲之優先順序。衝突即為依據該優先順序以重視之價值換取不重視之價值的交換行為;最低衝突則為以最不重視之價值換取最重視之價值的交換行為。若能以最低衝突進行交換即最能符合使用者價值觀;最符合使用者價值觀之決策則能滿足使用者之需求。透過本研究所發展之衝突解析演算法,將能夠找出與使用者價值觀最低衝突之代理人團隊,以使用者價值觀點出發,發掘出情境化任務,有效地滿足使用者需求。 / Most existing multi-agent systems (MAS) presume that the tasks to be resolved are given. However, this assumption sometimes renders the systems unrealistic. A sound mission discovery mechanism would exempt this assumption and offer flexibility and adaptation in resolving the user’s problem in dynamic complexity environments. The major challenge of mission discovery in MAS, in general, rests on how to associate missions to the user’s needs (i.e., the identification of the user’s needs). “Value” is anything that can give rise to exchange. For instance, if someone can help his friend no matter what the price he would pay for, then it means that the moral value surpasses the economics value for the case. Based on the theory of social exchange, this paper devises a Conflict Resolution Algorithm that aims to allocate an agent team of the members with the least value conflict so as to discover the contextualized missions that could fulfill the user’s needs.
53

多重移動平均選股法理論與實證 - 以台灣50、中型100及富櫃50成份股為例 / Theory and Evidence for Multi-period Moving Average Stock Selection - a Case Study of Constituent Stocks from Taiwan 50, Mid-Cap 100 and Gretai 50

官佑謙, You-Cian Guan January 1900 (has links)
本文改良金融投資技術分析操作方法中, 傳統的「單一移動平均」選股法為「多重移動平均」選股法, 其係以道氏理論上, 所謂的市場同時存在三種趨勢 (主要趨勢, 次級趨勢, 小型趨勢) 為基礎, 建立多重時間架構, 輔以移動平均線為股價趨勢判斷, 以及葛蘭碧八大法則之股價突破 (或跌破) 判斷原則作為操作訊號, 所彚整而提出。實證上, 採用2014年12月31日台灣證券交易所公告之台灣50、中型100, 以及富櫃50成分股為樣本, 並以2001年1月1日至2014年12月31日為回溯期間。在進行策略交易的模擬分析與績效差異檢定後, 實證結果發現, 多重移動平均選股法投資策略績效, 在統計分析上並無法較單一周期投資策略績效為優, 但卻能有效過濾沒必要的交易行為, 使突破買進之假訊號降低, 間接的降低交易次數及減少交易成本。 / This study enhanced from the traditional single period moving average for stock selection into multiple-period moving average counterpart. The theoretical foundation comes from the Dow Theory, which states that there exist three trends simultaneously, that is, major trend, secondary trend, and minor trend. Also, the Granville Rules suggest stock price breaking out may serve as entry and exit signal for trading. Our sample are grouped into three subsamples, Taiwan 50, Mid-Cap 100, Gretai 50. The sample period ranges from 2001/1/1 to 2014/12/31. Our empirical backtesting and performance test suggests that, contrary to our expectations, the multiple period method does not outperform its single period counterpart. However, the multiple period stock selection method may filter out false signals, and thereby reduce not only possible price risk associated with noisy trades but the accompanying transaction costs. / 摘要 I Abstract II 致謝詞 III 目錄 V 圖次 VII 表次 VIII 第一章 緒論 1 第一節 研究背景及動機 1 第二節 研究目的 2 第三節 研究對象與範圍 2 第四節 研究流程 4 第二章 文獻回顧 6 第一節 技術分析理論 6 一、技術分析基本邏輯 6 二、技術分析主要的型態類型 7 第二節 移動平均線的原理 9 一、簡單移動平均線的計算 9 二、移動平均線的常見應用 9 第三節 多重移動平均理論及選股法 11 一、多重移動平均的原理 11 二、多重移動平均的選股模式 11 第四節 相關研究文獻回顧與評析 11 一、過去研究文獻 11 二、文獻評析 16 三、本文假說推論 16 第三章 研究方法 17 第一節 傳統移動平均線選股模式 17 第二節 YC指標選股模式 17 第三節 選股模式績效差異檢定 19 第四節 資料來源與變數選取 19 第四章 實證分析 20 第一節 操作策略績效估計 20 第二節 操作策略績效比較 28 第三節 多重策略模型之適性歸納–由規模的角度 36 第五章 結論與建議 43 參考文獻 44 中文部份 44 英文部份 46 參考網址 46 圖次 圖1-4-1 研究流程圖 5 圖2-1-1 型態類技術理論的基本分類 6 圖2-1-2 市場同時存在三種趨勢 7 圖2-1-3 K線的基本構造 8 圖2-2-1 葛蘭碧(Granville)八大法則概念圖 10 表次 表1-3-1 台股之台灣50成分股 2 表1-3-2 台股之中型100成分股 3 表1-3-3 台股之富櫃50成分股 3 表2-4-1 過去研究文獻的整理 14 表4-1-1 台灣50成份股總交易次數及成本 20 表4-1-2 中型100成份股總交易次數及成本 22 表4-1-3 富櫃50成份股總交易次數及成本 26 表4-1-4 單一與多重模式下交易次數與進出場交易成本彚整 28 表4-2-1 台灣50成份股總報酬及總報酬率 28 表4-2-2 中型100成份股總報酬及總報酬率 30 表4-2-3 富櫃50成份股總報酬及總報酬率 34 表4-2-4 單一與多重策略下的平均總報酬與平均總報酬率彚整 36 表4-3-1 多重策略下總報酬率與市值之迴歸分析 36 表4-3-2 多重策略下總報酬率與股本之迴歸分析 37 表4-3-3 台灣50股本前20%成份股之策略績效及差異比較 37 表4-3-4 台灣50股本後20%成份股之策略績效及差異比較 38 表4-3-5 中型100股本前20%成份股之策略績效及差異比較 39 表4-3-6 中型100股本後20%成份股之策略績效及差異比較 40 表4-3-7 富櫃50股本前20%成份股之策略績效及差異比較 41 表4-3-8 富櫃50股本後20%成份股之策略績效及差異比較 42
54

家庭作業與學習成就關係之研究—以TIMSS與TEPS臺灣學生為例 / The Relationship between Homework and Learning Achievements: An Example of Taiwan Students from TIMSS and TEPS

陳俊瑋 Unknown Date (has links)
本研究旨在了解家庭作業與學習成就的關係。為達研究目的,本研究以階層線性模式分析「國際數學與科學教育成就趨勢調查」2007年4年級學生資料;2007年8年級學生資料;以及2011年8年級學生資料,接著,本研究再以結構方程模式的長期追蹤交叉延宕模式,分析「臺灣教育長期追蹤資料庫」2001年、2003年及2005年追蹤樣本學生資料,本研究主要發現: 一、臺灣4年級學生的學生層次數學家庭作業時間對數學學習成就有顯著負向地影響效果;學生層次科學家庭作業時間對科學學習成就也有顯著負向地影響效果。 二、臺灣4年級學生的班級層次數學家庭作業頻率對數學學習成就沒有顯著地影響效果;班級層次科學家庭作業頻率對科學學習成就也沒有顯著地影響效果。 三、臺灣8年級學生的學生層次數學家庭作業時間對數學學習成就有顯著正向地影響效果;學生層次科學家庭作業時間對科學學習成就也有顯著正向地影響效果。 四、臺灣8年級學生的班級層次數學家庭作業頻率對數學學習成就有顯著正向地影響效果;班級層次科學家庭作業頻率對科學學習成就也有顯著正向地影響效果。 五、臺灣2001年7年級陸續追蹤至2005年11年級的學生,其家庭作業時間與學習成就有顯著正向地相互影響效果。 / This study aimed analyze the relationship between homework and learning achievements. Hierarchical linear modeling was used to analyze the 4th grade of elementary school students from Trends in International Mathematics and Science Study (TIMSS) 2007, 8th grade of junior high school students from TIMSS 2007, and 8th grade of junior high school students from TIMSS 2011. Moreover, structural equation modeling with cross-lagged panel modeling was used to analyze the core panel sample data from Taiwan Education Panel Survey (TEPS) in 2001, 2003, and 2005. The major findings were as follows: 1. Taiwan 4th grade of elementary school students’ student-level mathematic homework time could negative predict the mathematic learning achievements significantly, and student-level science homework time could also negative predict the science learning achievements significantly. 2. Taiwan 4th grade of elementary school students’ class-level mathematic homework frequency could not predict the mathematic learning achievements significantly, and class-level science homework frequency could also not predict the science learning achievements significantly. 3. Taiwan 8th grade of junior high school students’ student-level mathematic homework time could positive predict the mathematic learning achievements significantly, and student-level science homework time could also positive predict the science learning achievements significantly. 4. Taiwan 8th grade of junior high school students’ class-level mathematic homework frequency could positive predict the mathematic learning achievements significantly, and class-level science homework frequency could also positive predict the science learning achievements significantly. 5. Taiwan 7th grade of junior high school students to 11th grade of senior high school students’ homework time could positive predict the subsequent learning achievements significantly, and learning achievements could also positive predict the subsequent homework time significantly.
55

多重市場競爭與價格離散之關聯 : 以美國境內航空市場為例 / Does multimarket contact matter for price dispersion in the airline industry?

劉亭彣, Liou, Ting-Wun Unknown Date (has links)
本文以美國境內航空市場為例,探討多重市場接觸與價格離散的關聯,並研究大型航空公司併購案前後多重市場接觸對航空公司競爭策略的影響。本研究發現:(一) 相互容忍說於併購案發生前後皆成立。(二) 相較於考量擴大市場的市佔率,航空公司更應該關注與競爭者間的競爭關係。(三) 併購案發生前後,航空公司的訂價行為都深受競爭對手的競爭策略影響。(四) 併購案發生前,因競爭者多,市場上航空公司平均市佔率的大小是航空公司可採取競爭手段重要因素之一。在最大的1000 個市場中,雖然每家航空公司的市場力量不大,航空公司仍可採取價格競爭,然若是對手間聯合懲罰,則航空公司不敢採取激進手段,且多重市場接觸越多,價格離散程度越大。而在次要競爭的市場中,則因航空公司的平均市占率是最大的1000 個市場的兩倍,因此航空公司並未有明顯競爭行為。但若考量競爭對手間的碰面次數,則多重市場接觸與不同分位價格關係為正,且多重市場接觸越多,價格離散程度越低。併購案發生後,因航空公司間彼此箝制力量大,與競爭對手間的碰面次數越多,越傾向隱性勾結,且高價位的價格上升較低價位價格多,使價格離散程度越大。 / In this paper, we discuss whether multimarket contact matters for price dispersion in the U.S. airline industry, and compare the influence of multimarket contact on airlines’ competition strategies before and after airline mergers and acquisitions. We find that: (a) Before and after the mergers, mutual forbearance exists. (b) In contrast to an airline‘s market share, the relationship between airlines and itself plays a more important role in its pricing strategy.(c) Before and after the mergers, airline companies’pricing strategies are significantly affected by their competitors’strategies. (d) Before the mergers, because of the intense competition, it is the size of the competitors‘ market share that the company decide whether to take aggressive strategies. In the top 1000 competitive markets,airline companies will take aggressive actions to get more passengers for the punishment from its competitor is an incredible threat, however, if competitors collude together, airline companies will hardly dare to cut price. And the effect of an increase in multimarket contact on price dispersion is positive and significant. In the second competitive markets, since the average market share is twice bigger than in the top 1000 markets, airlines prefer not to participate in cut-throat competition. However, if competitors collude, then airline companies will cooperate together, and the effect of an increase in multimarket contact on price dispersion is negative and significant. After the mergers, increase in contacts with competitors would facilitate mutual forbearance and increase price dispersion and higher-percentile prices will increase more than lower-percentile prices.
56

Synthetic Studies on the Al=Al Doubly Bonded Species and Elucidation of Their Reactivity / アルミニウム間二重結合化学種の合成研究とその反応性の解明

Nagata, Koichi 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19523号 / 理博第4183号 / 新制||理||1601(附属図書館) / 32559 / 京都大学大学院理学研究科化学専攻 / (主査)教授 時任 宣博, 教授 丸岡 啓二, 教授 大須賀 篤弘 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
57

肺癌之研究及保單設計 / Study and price insurance for the lung cancer

葉步釩, Ye, Bu Fan Unknown Date (has links)
本次研究使用全民健康保險研究資料庫2005承保抽樣歸人檔(LHID2005),共40萬人的承保資料,針對肺癌患者的特徵進行分析,並與美國國家癌症研究所的肺癌資料作比較,罹患肺癌的人數都呈現男性多於女性,罹癌年齡的最高峰同樣落在65歲至74歲。 接著,將門診處方及治療明細檔和住院醫療費用清單明細檔進行彙整,整理出肺癌患者在2005年至2012年之間的門診費用以及住院費用,並比較不同項目的差距及特徵,門診費用以用藥明細點數最高,住院花費前五名的項目為葯費、病房費、放射線診療費、檢查費以及治療處置費。 最後,建構肺癌治療的多重型態模型,治療方式包含手術治療、放射線治療、化學治療,估計不同狀態之間的轉換力,進而算出五年定期躉繳肺癌保單之純保費。 / This study used Longitudinal Health Insurance Database 2005 (LHID2005) from Taiwan’s National Health Insurance Research Database (NHIRD). Screening the 400,000 insured of NHIRD to select the lung and bronchus cancer patients. This study analyzed and described their characteristics. Furthermore, it compared Taiwan’s lung and bronchus cancer data with the data in the United States derived from National Cancer Institute of the USA. The results revealed that the number of male patients is more than female patients and lung cancer is most frequently diagnosed among people aged 65-74 in both countries. Another aim was to sum up the lung cancer medical cost in 2005 to 2012 from NHIRD database, including ambulatory care expenditures by visits and inpatient expenditures by admissions. The highest cost of outpatients was medicine fee. The top five inpatient expenditures were medicine fee, ward fee, radiation therapy fee, inspection fee and therapeutic treatment fee. Finally, this study constructed a multiple state model of lung cancer treatment, including surgery, radiotherapy, chemotherapy. Estimating the transition intensities from multiple state model to calculate the pure premium of a five-year lung cancer policy.
58

應用數量方法於解決多重目標規劃問題之研究

戚樹誠, Qi, Shu-Cheng Unknown Date (has links)
本研究旨在提出多重目標決策理論之分析模式,并考慮實際管理者之使用,以作為管 理決策過程的有效工具。 不論個人的、組織的問題,不可避免存在不同且彼此衝突之目標。對於單一目標,傳 統作業研究理論已提供相當完整、審密的分析,然而,對於多重目標問題,則因涉及 層面遠較複雜,理論發展至近年才漸豐富,本文便研析至今之各種學說,并嘗試引入 實際決策情境討論。 全文乃以觀念性分析邏輯配合實際操作,其內容計有: 一、決策者的價值與偏好具體化-利用屬性分析及權的量度。 二、線型多目標規劃模型 三、目標規劃模型 四、互動規劃模型 五、實際操作的探討 為使其易於為管理者接受,筆者并建議在使用時宜採行的原則,以作選擇模型之參考 ,最後并提及今後的發展方向,以展望此學科邁向更嚴謹、系統化的整套理論體系。
59

穩定性與多重性-以二部門體系動態調整方式為例 / Stability and indeterminacy --the dynamic adjustment of two-sector economy

連科雄, Lian, Ke-Shaw Unknown Date (has links)
本篇論文試圖藉由比較一個產業生產技術為固定規模報酬的經濟體系,如何因外部因素的影響而改變其動態調整方式。在此考慮的外部因素有資本移動的開放與否、生產要素的外部性、及政府對要素報酬的課稅。考慮各種因素後,所得出的結論為在生產函數為Cobb-Douglas型式且產業生產技術為固定規模報酬的情況下: 1.多重均衡路徑在資本帳封閉時期唯有效用函數為特例時才能使其出現,但在資本自由移動時期對於所有的效用函數型態皆會成立。 2.其他條件保持不變之下,單獨存在生產要素外部性或是對要素所得課稅皆可使體系存在多重均衡路徑。 3.其他條件保持不變之下,若生產要素外部性與要素所得稅皆同時存在時,可使體系存在唯一的穩定馬鞍路徑。
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伴隨估計風險時的動態資產配置 / Dynamic asset allocation with estimation risk

湯美玲, Tang, Mei Ling Unknown Date (has links)
本文包含關於估計風險與動態資產配置的兩篇研究。第一篇研究主要就當須估計的投資組合其投入參數具有高維度特質的觀點下,探究因忽略不確定性通膨而對資產配置過程中帶來的估計風險。此研究基於多重群組架構下所發展出的新投資決策法則,能夠確實地評價不確定性通膨對資產報酬的影響性,並在應用於建構大規模投資組合時,能有效減少進行最適化投資決策過程中所需的演算時間與成本。而將此模型應用於建構全球ETFs投資組合的實證結果則進一步顯示,若在均值變異數架構下,因建構大型投資組合時須估計高維度投入參數而伴隨有大量估計風險時,參數估計方式建議結合採用貝氏估計方法來估算資產報酬的一階與二階動差,其所對應得到的投資組合樣本外績效會比直接採用歷史樣本動差來得佳。此實證結果亦隱含:在均值變異數架構下,穩定的參數估計值比起最新且即時的參數估計資訊對於投資組合的績效來得有益。同時,若當投入參數的樣本估計值波動很大時,增加放空限制亦能有利投組樣本外績效。 第二篇文章則主要處理當處於對數常態證券市場下時,投資組合報酬率不具有有限動差並導致無法在均值變異數架構下發展出最適化封閉解時的難題。本研究示範此時可透過漸近方法的應用,有效發展出在具有放空限制下,考量了估計風險後的簡單投資組合配置法則,並且展示如何將其應用至實務上的資產配置過程以建構全球投資組合。本文的數值範例與實證模擬結果皆顯示,估計風險的存在對於最適投資組合的選擇有實質的影響,無估計風險下得出的最適投資組合,不必然是存有估計風險下的最適投資組合。此外,實證模擬結果亦證明,當存有估計風險時,本文所發展的簡單法則,能使建構出的投資組合具有較佳的樣本外績效表現。 / This dissertation consists of two essays on dynamic asset allocation with regard to dealing with estimation risk as being in different uncertainties in the mean-variance framework. The first essay concerns estimation errors from disregarding uncertain inflation in terms of the need in estimating high-dimensional input parameters for portfolio optimization. This study presents simplified and valid criteria referred to as the EGP-IMG model based on the multi-group framework to be capable of pricing inflation risk in a world of uncertainty. Empirical studies shows the proposed model indeed provides a smart way in picking worldwide ETFs that serves well to reduce the amount of costs and time in constructing a global portfolio when facing a large number of investment products. The effect of Bayesian estimation on improving estimation risk as the decision maker is subject to history sample moments for input parameters estimations is meanwhile examined. The results indicate portfolios implementing the Stein estimation and shrinkage estimators offer better performance compared with those applying the history sample estimators. It implicitly demonstrates that yielding stable estimates for means and covariances is more critical in the MV framework than getting the newest up-to-date parameters estimates for improving portfolio performance. Though short-sales constraints intuitively should hurt, they do practically contribute to uplift portfolio performance as being subject to volatile estimates of returns moments. The second essay undertakes the difficulty that the probability distribution of a portfolio's returns may not have finite moments in a lognormal-securities market, and thus leads to the arduous problem in solving the closed-form solutions for the optimal portfolio under the mean-variance framework. As being in a lognormal-securities market, this study systematically delivers a simple rule in optimization with regard to the presence of estimation risk. The simple rule is derived accordingly by means of asymptotic properties when short sales are not allowed. The consequently numerical example specifies the detailed procedures and shows that the optimal portfolio with estimation risk is not equivalent to that ignoring the existence of estimation risk. In addition, the portfolio performance based on the proposed simple rule is examined to present a better out-of-sample portfolio performance relative to the benchmarks.

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