• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 153
  • 129
  • 24
  • 1
  • Tagged with
  • 154
  • 154
  • 57
  • 55
  • 48
  • 43
  • 39
  • 37
  • 36
  • 34
  • 32
  • 24
  • 23
  • 22
  • 21
  • 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.
151

跳躍相關風險下狀態轉換模型之選擇權定價:股價指數選擇權實證分析 / Option pricing of a stock index under regime switching model with dependent jump size risks: empirical analysis of the stock index option

林琮偉, Lin, Tsung Wei Unknown Date (has links)
本文使用Esscher轉換法推導狀態轉換模型、跳躍獨立風險下狀狀態轉換模型及跳躍相關風險下狀態轉換模型的選擇權定價公式。藉由1999年至2011年道瓊工業指數真實市場資料使用EM演算法估計模型參數並使用概似比檢定得到跳躍相關風險下狀態轉換模型最適合描述報酬率資料。接著進行敏感度分析得知,高波動狀態的機率、報酬率的整體波動度及跳躍頻率三者與買權呈現正相關。最後由市場驗證可知,跳躍相關風險下狀態轉換模型在價平及價外的定價誤差皆是最小,在價平的定價誤差則略高於跳躍獨立風險下狀態轉換模型。 / In this paper, we derive regime switching model, regime switching model with independent jump and regime switching model with dependent jump by Esscher transformation. We use the data from 1999 to 2011 Dow-Jones industrial average index market price to estimate the parameter by EM algorithm. Then we use likelihood ratio test to obtain that regime switching model with dependent jump is the best model to depict return data. Moreover, we do sensitivity analysis and find the result that the probability of the higher volatility state , the overall volatility of rate of return , and the jump frequency are positively correlated with call option value. Finally, we enhance the empirical value of regime switching model with dependent jump by means of calculating the price error.
152

結合家庭、病例及病例-對照分析中疾病遺傳訊息的統計方法 / Statistical Methods for Combining Genetic Association Information from Family, Case-Only and Case-Control Analyses

林惠文, Lin,Hui Wen Unknown Date (has links)
近年來,基因與疾病之關聯分析 (association analysis) 越來越受到研究學者重視,因為在複雜性疾病與易感性基因之探討中 傳統的連鎖方法 (linkage method) 已不適用,所以複雜性疾病與易感性基因的關聯分析也蓬勃發展起來。在本文中我們主要是在探討 關聯分析中以家庭為研究資料與以群體為研究資料之間的優缺點,進而取長補短提出結合兩種資料之新的關聯分析方法 來增加估計與檢定之效力。我們同時考慮環境因素,探討基因因素與環境因素之交互作用。 本研究共分為三部份。第一部份探討如何整合病例-父母/病例-同胞 (case-parent/case-sibling) 與病例-對照 (case-control) 研究。我們提出一個加權最小平方 (Weighted Least Squares) 的方法將病例-父母/病例-同胞與病例-對照分析之估計式加以結合,以增進統計檢定之效力。 第二部分旨在探討基因-環境之交互作用。我們提出一個二階段研究設計法。在第一階段研究中,先收集病例資料; 在第二階段研究中,再收集其相對應之控制組資料。我們提出一個迴歸估計式以結合第一階段之單純病例分析(case-only analysis) 與第二階段之病例-對照分析。此建議之估計式即使在基因因子與環境因子 獨立之條件 (此條件為單純病例分析所必需) 不成立的情形下,依然可得出正確之統計推論。 第三部份旨在探討群體分層 (population stratification) 存在 之情形下,基因-環境之交互作用。我們提出一個二階段研究設計,以病例資料為第一階段資料, 再從病例資料中隨機抽取一部份病例患者之父母資料為第二階段資料。我們提出一個迴歸估計式結合單純病例研分析與病例-父母分析之估計式。 此新估計式即可整合單純病例分析與病例-父母分析,同時在群體分層存在之情形下,仍可得出有效之統計推論。 / In recent years, there are increasing attention to association studies, because linkage method will not be suitable under complex disease and susceptible genes. In the thesis, we are probing into association of family study and population study. And we combine family study and population study for increased efficiency of association method. We also consider interesting studies about gene-environment interactions. The thesis contains three projects. The first project focuses on examining when and how the two sources of information offered by such studies, one from the case-parent/case-sibling analysis, and the other from the case-control analysis with data from affected subjects and unrelated controls, can be integrated to enhance statistical power. We propose a weighted least-squares approach to linearly and optimally combine separate estimators from the case-parent/case-sibling and the logistic regression analysis for the association parameters. In the second project, we focus on examining the situation of gene-environment interaction. We propose a two-stage design. In the first stage, we collect patient data, and we seek out control data with respect to cases in the second stage. We propose regression analysis estimation in order to combine the case-only analysis in the first stage and the case-control analysis in the second stage. This estimation earns the correct statistical inference when genes and environment factors are not independent. In the third project, we explore gene-environment interactions under population stratification. We propose a two-stage design. In the first stage, we collect patient data, and we randomly collect a partial data of patient's parent from the cases in the second stage. We propose regression analysis estimation in order to combine the case-only analysis and the case-parent analysis. This estimation can combine the case-only analysis and the case-parent analysis, and attains effective statistical inference under population stratification.
153

狀態轉換下利率與跳躍風險股票報酬之歐式選擇權評價與實證分析 / Option Pricing and Empirical Analysis for Interest Rate and Stock Index Return with Regime-Switching Model and Dependent Jump Risks

巫柏成, Wu, Po Cheng Unknown Date (has links)
Chen, Chang, Wen and Lin (2013)提出馬可夫調控跳躍過程模型(MMJDM)描述股價指數報酬率,布朗運動項、跳躍項之頻率與市場狀態有關。然而,利率並非常數,本論文以狀態轉換模型配適零息債劵之動態過程,提出狀態轉換下的利率與具跳躍風險的股票報酬之二維模型(MMJDMSI),並以1999年至2013年的道瓊工業指數與S&P 500指數和同期間之一年期美國國庫劵價格為實證資料,採用EM演算法取得參數估計值。經由概似比檢定結果顯示無論道瓊工業指數還是S&P 500指數,狀態轉換下利率與跳躍風險之股票報酬二維模型更適合描述報酬率。接著,利用Esscher轉換法推導出各模型下的股價指數之歐式買權定價公式,再對MMJDMSI模型進行敏感度分析以評估模型參數發生變動時對於定價公式的影響。最後,以實證資料對各模型進行模型校準及計算隱含波動度,結果顯示MMJDMSI在價內及價外時定價誤差為最小或次小,且此模型亦能呈現出波動度微笑曲線之現象。 / To model asset return, Chen, Chang, Wen and Lin (2013) proposed Markov-Modulated Jump Diffusion Model (MMJDM) assuming that the Brownian motion term and jump frequency are all related to market states. In fact, the interest rate is not constant, Regime-Switching Model is taken to fit the process of the zero-coupon bond price, and a bivariate model for interest rate and stock index return with regime-switching and dependent jump risks (MMJDMSI) is proposed. The empirical data are Dow Jones Industrial Average and S&P 500 Index from 1999 to 2013, together with US 1-Year Treasury Bond over the same period. Model parameters are estimated by the Expectation-Maximization (EM) algorithm. The likelihood ratio test (LRT) is performed to compare nested models, and MMJDMSI is better than the others. Then, European call option pricing formula under each model is derived via Esscher transformation, and sensitivity analysis is conducted to evaluate changes resulted from different parameter values under the MMJDMSI pricing formula. Finally, model calibrations are performed and implied volatilities are computed under each model empirically. In cases of in-the-money and out-the-money, MMJDMSI has either the smallest or the second smallest pricing error. Also, the implied volatilities from MMJDMSI display a volatility smile curve.
154

台指選擇權之市場指標實證分析

吳建民, Wu,Jian-Min Unknown Date (has links)
本研究有系統地收集了2003年8月12日到2005年9月30日止共495個交易日的台指期貨、選擇權市場裡P/C量、P/C倉、隱含波動率(AIV)、不同天數的歷史波動率等收盤資料,進行這些因素與行情走勢間的關係,以及因素彼此的互動性。結果證實分析台指選擇權指標是需要區分金融重大衝擊前後期間,以及區分漲勢、跌勢、盤整的各期間,各期間的選擇權指標均會有不同意涵。 本論文證實使用結構轉換的Chow-ARMA(2,1)模型可能比較符合模擬指數 實況,且GARCH(1,1) 模型也很適合描述台期指貨波動度預測力。在選擇權指標方面:P/C量與AIV與台指期貨呈現負相關,P/C倉與台指期貨正相關。其中以P/C倉對指數漲跌的影響程度最大、P/C量的影響程度次之、AIV影響程度最小。若把隱含波動率區分成買權與賣權之各個波動率更有效地預測行情走勢,在大跌期間的買賣權隱含波動率更能表現出優越的預測能力,其中前兩期的賣權隱含波動率(PIV)更是效率性指標, 實證結果使用20天的歷史波動率比較能貼近選擇權市場的變化,跟過去教 科書慣用的90天不同。若比較歷史波動率與隱含波動率間的關係,結論是當「大跌期」歷史波動率大於買權隱含波動率(CIV)時,買權是會被低估的,其他的各種假設條件均不成立。理由有二:一是市場效率性決定了是否可使用隱含波動率與歷史波動率之間的高低關係。二是「大跌時期」相對於「大漲時期」的市場資訊被反應的更敏銳,而在「大跌時期」的賣權價格反應比買權價格反應更快速敏銳。 本研究推論的Chow-ARMA(2,1) 台指期貨模型、GARCH(1,1) 波動率模型、P/C量-P/C倉-AIV的多變數模型、FMA20/XIV模型等等在研判指數變化上具有參考價值,進一步均可以做為選擇權操作策略參考依據之一。

Page generated in 0.0193 seconds