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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.
91

應用統計方法鑑定模擬模式有效性之研究

何沐仙, He, Mu-Xian Unknown Date (has links)
本論文主要在探討鑑定模擬模式之問題,提出數種可行的統計方法,用以檢定模擬模 式之適合度,並以判定分析討論對模擬模式之認定。首章為緒論,說明本人研究此一 問題之動機、目的、方法與範圍,並簡要敘述本論文之架構及各章節之安排。 第二章論及有關鑑定模擬模式之問題,包括討論鑑定之一般論點、多階段鑑定,以及 統計觀念之應用和對模擬模式分析之,第三章專門探討對模擬模式之適合度檢定,包 括卡方檢定、梅恩─懷特尼檢定、希爾不等係數之指標、變異數分析等方法,並討論 對模式之改良。第四章乃以判定分析並考慮成本因素,討論對模擬模式之認定。第五 章是結論。
92

加油站人員配置問題之研究

林文斌, Lin, Wen-Bin Unknown Date (has links)
本研究以大台北地區所屬的五十個加油站為研究母體,利用簡單隨機抽樣,抽取其中 的二十五個站為觀測紀錄之樣本站,紀錄其車次到達,加油方式、加油量、付款方式 等資料,並以卡方及克斯檢定決定各變數之機率分配型態,作為等候線模擬之投入變 數。而後就模擬結果做迴歸及變異數分析,以決定在各種不同的人力配置,設備布置 ,車次,加油方式、油量、付款方式下的加油效率。據此求得加油站人力配置之一般 化模式,以作為加油站人力配置之參考。
93

設備更新及其計劃之實例研究

陳清文, Chen, Qing-Wen Unknown Date (has links)
一、研究動機:設備更新是經常面臨的問題。設備更新分析已發展出多種模式,可是 廠商未能充分使用,乃引發本研究對其中問題再做探討。 二、研究架構:(一)列舉設備更新面臨的問題。(二)探討各種模式是否解決前項問題 并做小幅度修正。(三)比較與選用模式。 三、研究重點:(一)綜合整理各種更新模式并比較應用。(二)時間幅度及不確定性對 各種模式及決策的影響。(三)設備更新計劃之擬定。(四)實證研究。 四、研究方法:(一)由文獻收集各種更新模式。(二)應用動態規劃法、隨機法、模擬 法等新式方法。(三)各種模式做敏感度分析,以供決策參考。
94

電子計算機模擬在不确定情況下折舊之應用

余晉文, Yu, Jin-Wen Unknown Date (has links)
本文共一冊,分七章,約三萬餘言,主旨是應用電算機模擬法於折舊的問題上,因為 折舊問題本身牽涉到許多不確定性,故適合採用此法來加以探討。玆約略說明各章內 容如下: 第一章:說明研究之目的、理由、動機及方法等。 第二章:說明電算機模擬法之意義、基本理論、功用及優劣點。 第三章:說明折舊之重要性及不確定性。 第四章:應用模擬法探討通貨膨脹情況下折舊費用的低估對凈利之影響。 第五章:應用模氦法以估計折舊費用。 第六章:應用模擬法探討折舊費用對投資決策的影響。 第七章:結論。
95

多資產結構型商品之評價與避險--利用Quasi-Monte Carlo模擬法

粘哲偉 Unknown Date (has links)
結構型商品,這種風險介於固定收益證券和股票之間的產品,甫上市以來,便廣受投資人的青睞,不僅提供保障本金的需求,更賦予參與股市上漲的獲利。且自從2004年之後,隨著目前景氣逐步回升,股票市場也預期會跟著上揚,於是連結股權的結構型商品也不斷地被推出,而其所隱含選擇權逐漸以連動多資產和具有新奇路徑相依條款為主,而使得在評價上,我們所面對的是高維度的問題,一般在處理高維度問題上,皆以傳統蒙地卡羅模擬法來因應。但因其緩慢的收斂速度,成為應用上的最大缺點,而且在處理高維度問題上所需耗費的模擬時間更為顯著。 本論文主要貢獻可分為兩點:第一,在應用準蒙地卡羅法來對多資產結構型商品評價,並採用Silva(2003)和Acworth, Broadie, and Glasserman(1998)的方法,來對準蒙地卡羅法作改善,並利用二檔市面上存在的結構型商品---高收益鎖定型連動債券和優選鎖定連動債券進行評價,結果發現改善後的準地卡羅法,其評價效率高於蒙地卡羅法和反向變異蒙地卡羅法。第二,本文還對高收益鎖定型連動債券提出delta避險策略,透過先計算選擇權對報酬率的delta,再轉換為所需持有股票的部位,最後發現所建立的避險組合能夠完全支應每年到期時所應付給投資人的債息,以及在避險時所需借款的部份,表示此一策略應為可行的避險策略,可供券商作避險上的參考。
96

住宅抵押貸款債權證券之評價與分析

林進南 Unknown Date (has links)
本論文將針對不同證券化標的型態和考量房貸戶提前清償差異之情況下,來推導MBS的評價公式。其中可發現任何證券化標的型態的MBS評價過程都能從可調整利率住宅抵押貸款的角度來進行,因此建構出的一般化評價模型便可作為其他新奇房貸設計的參考依據。並且透過蒙地卡羅法來模擬可調整利率住宅抵押貸款的理論價值,同時採用反向變異法來達到加速模擬過程的目的,以便於更趨近於真正的理論價值。而且也針對建構模型中的各項參數、誘因函數參數以及其他影響MBS理論價值的因素進行敏感度分析。
97

獨立與非獨立性資料之多重比較

李昀叡 Unknown Date (has links)
同時比較多個樣本間的差異,可用ANOVA來檢定,但ANOVA只能得到樣本間有差異的訊息,無法明確指出是哪些樣本間有差異,需要使用多重比較找出樣本間的差異。本文主要探討相關的離散型資料的多重比較,以型I誤差與檢定力兩指標找出最適的多重比較法。本文依序探討獨立的連續型資料、相關的連續型資料、獨立的離散型資料、相關的離散型資料,並針對相關型的資料提出修正法。綜合型I誤差與檢定力兩指標來看,在樣本間的平均差異小時,Shaffer’s first procedure Test (1986)、Procedure 4 by Bergmann and Hommel (1988)為兩兩比較下較佳的修正法,Hochberg Test (1988)為多對ㄧ比較下較佳的修正法;樣本間平均差異大時,Bonferroni 為兩兩比較下較佳的修正法,Hochberg (1988)、Simes (1986)為多對ㄧ比較下較佳的修正法。 / Analysis of variance (ANOVA) is usually applied to check whether there are differences among more than two treatments. However, even there are differences, multiple comparison procedures are still needed to determine which pair(s) of treatments are different. In this study, we use simulation to compare the frequently used multiple comparison procedures, including many-to-one and pair-wise, and type-I error and power are used to measure the performance of procedures. Two types of data were considered, independently and correlated distributed data. If the differences among treatments are small, Shaffer’s first procedure test (1986) and Procedure 4 by Bergmann and Hommel (1988) are the best in pair-wise case, and Hochberg test (1988) is the best in many-to-one case. If the differences among treatments are large, the Bonferroni procedure is the best in pair-wise case, and the procedures by Hochberg (1988) and Simes (1986) are the best in many-to-one case.
98

模擬最適化運用於資產配置之驗證 / The Effectiveness of the Asset Allocation Using the Technique of Simulation Optimization

劉婉玉 Unknown Date (has links)
本文利用模擬最適化(Simulation Optimization)的技術,來找出適合投資人之最佳資產配置。模擬最適化係為一種將決策變數輸入而使其反應變數得到最佳化結果之技術,在本篇中,決策變數為各種投資標的之資產配置,而反應變數則為投資結果之預期報酬與標準差,模擬最適化可視為一種在可行範圍內尋求最佳解之過程。本篇中模擬最適化之方法係採演化策略法,最適化問題則為具放空限制之多期架構。我們亦進一步與各種傳統的投資保險策略比較,包括買入持有策略(Buy-and-Hold)、固定比例策略(Constant Mix)、固定比例投資保險策略(Constant Proportion Portfolio Insurance)及時間不變性投資組合保險策略(Time-Invariant Portfolio Protection),以驗證模擬最適化的有效性,並以多種評估指標來衡量各種策略績效之優劣。 由實證結果發現,利用模擬最適化求解出每月的最適資產配置,雖然造成每期因資金配置比例變動而提高波動性,另一方面卻能大幅的增加報酬率。整體而言,模擬最適化技術的確能夠有效提升投資績效,使得最終財富增加,並且得到較大的夏普指數及每單位風險下較高的報酬。 / This paper applied simulation optimization technique to search for the optimal asset allocation. Simulation optimization is the process of determining the values of the decision variables that optimize the values of the stochastic response variable generated from a simulation model. The decision variables in our case are the allocations of many kinds of assets. The response variable is a function of the expected wealth and the associated risk. The simulation optimization problem can be characterized as a stochastic search over a feasible exploration region. The method we applied is the evolution strategies and the optimization problem is formulated as a multi-period one with short-sale constraints. In order to verify the effectiveness of simulation optimization, we compared the resulting asset allocation with allocations obtaining using traditional portfolio insurance strategies including Buy-and-Hold, Constant Mix, Constant Proportion Portfolio Insurance, and Time-Invariant Portfolio Protection. We also used many indexes to evaluate performance of all kinds of strategies in this paper. Our empirical results indicated that using simulation optimization to search for the best asset allocation resulted in large volatilities, however, it significantly enhanced rate of return. As a whole, applying simulation optimization indeed gets the better performance, increases the final wealth, makes Sharpe Index large, and obtains the higher return under per unit risk.
99

最低稅負制對營利事業影響之模擬研究

黃銘啟 Unknown Date (has links)
本研究主要在探討最低稅負制實施後,對我國上市櫃電子業稅負影響情況為何。不同於以往文獻以營利事業所得稅申報資料來進行模擬分析,本研究以財務報表之所得稅附註資料進行模擬設算。不用營利事業所得稅申報資料進行模擬乃因該資料取得不易,並非一般投資大眾所能獲取之資料,本研究乃嘗試使用財務報表之所得稅附註資料進行模擬設算,希望能模擬出最低稅負制之實施對電子業之影響情形。此外,本研究利用模擬設算之基本稅額與一般所得稅額之差額當成依變數,建立一條迴歸式,希望能從中發現最低稅負制實施後,受影響之公司具有哪些特性,以供投資人在選擇投資標的時有所參考。 本研究經過篩選後,對我國上市櫃電子業的其中206家公司進行民國93年及94年的模擬設算。其設算結果為平均每年每家公司會增加1,000多萬元的稅負,而約有3成的公司將會受到影響。實證結果亦證實最低稅負制實施後,對於我國上市櫃電子業確實有明顯的租稅負擔。迴歸結果則發現,對於股東可扣抵稅額愈小、研發費用愈高、獲利能力愈佳及公司規模愈大之公司會有較明顯的租稅負擔。此種情形是否對這些公司之競爭力造成不利影響,非常值得關心。此外,電子業競爭相當激烈,必須投入相當多的研究發展費用與相關的重大投資,而經本研究結果也證實,研發費用愈高的公司,在最低稅負實施後,將補繳愈多的稅額,未來公司在從事這些支出時,應更加審慎評估。 / This study investigates the effects that the implementation of Alternative Minimum Tax (AMT) has on our electronic industries publicly listed in Taiwan Stock Exchange. Past studies often utilized the income tax reported by profit-seeking enterprises; nevertheless, these data are not accessible to the public. In view of this, the current study attempts to simulate calculating the appendix of income tax in financial statements, with an aim to simulating the impacts that implementation of AMT exerts on the electronic industries. Furthermore, as the difference between the simulated Basic tax and Regular tax is the dependent variable, established is a regression model, with which the characteristics of the companies influenced by the implementation of AMT can be identified, so that investors can refer to when they choose investing targets. After the sampling, the simulating calculation on two years, i.e. 2004 and 2005 has been conducted among 206 companies among the publicly listed electronic industries. The results of calculation demonstrate that each company would have more than ten million taxes each year and approximately thirty percent of the firms will be influenced by the implementation of AMT. Empirical results also confirm that there will be significant tax burdens after AMT takes effect. Moreover, the outcomes of regression analysis indicate that more salient tax burdens will be imposed upon the firms with larger size, smaller shareholder deductible tax, higher research funds, and more profitability.
100

台灣地區死亡率APC模型之研究 / An Empirical Study of Age-Period-Cohort Model of Mortality Rates of Taiwan Area

王郁萍, Wang,Yu-Ping Unknown Date (has links)
台灣地區居民近年的死亡率下降速度加快,使得我國國民的平均壽命在公元2000年已超過美國,成為長壽的國家之一。其中我國國民死亡率的下降幅度因年齡而不同,且各個年代、世代也不相同,與APC(Age-Period-Cohort)模型採年齡、年代與世代三個因子分析死亡率頗為一致,因此本文計畫以APC模型研究台灣的死亡率。然而,由於「年代=年齡+世代」之線性相關,參數估計值有甄別問題(Identification Problem),使得參數估計值不唯一。 文獻中有不同方法解決APC模型的參數估計問題,近年又有Fu(2000)提出之本質估計量(Intrinsic Estimator),可直接解決參數估計及其變異數。因此本文首先以電腦模擬驗證本質估計量,以及過去其他估計方法,檢測這些方法是否可得出理論的結果。本文的第二部分則以西元1961至2005年的資料探討APC模型的實用性,分析APC與Lee-Carter模型的優劣;研究發現APC模型用於估計死亡率時,整體而言雖不如Lee-Carter模型,但可彌補Lee-Carter模型在高年齡有較大誤差的不足,唯在年輕族群則仍有改善空間,未來或可考慮APC與Lee-Carter模型的結合。 / The mortality rates in Taiwan area have been experiencing dramatic decreases in recent years. The life expectancy has surpassed that in the United States in 2000 and Taiwan has become one of the longevity countries. Besides, the falling of mortality rates varies in different age, period, and cohort groups, which corresponds to the APC (Age-Period-Cohort) model. Therefore, the goal of this paper is to study the mortality rates in Taiwan area with APC model. However, due to the linear dependency of age, period and cohort (Period = Age + Cohort), there is the identification problem, that is, the parameter estimates are not unique. A number of solutions to the identification problem in APC model have been provided in the literature. Fu (2000) introduce a new estimator, the Intrinsic Estimator (IE), which can solve parameter estimates and variance directly. In the first part of this research, computer simulation is conducted to examine the IE, compared with other methodologies. In the second part of this research, data from 1961 to 2005 are used for verifying the validity of APC model in fitting mortality rates, and we analyze the strengths and weaknesses between the APC and Lee-Carter model. The results from our study indicate that the APC model in estimating mortality rates does not show as well as the Lee-Carter model as a whole. However, the APC model performs better than the Lee-Carter model for the elderly mortality rates, but is still needed to be improved in young groups. In the future, it can be considered to combine the APC and Lee-Carter model.

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