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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.
101

醫療資源優先配置決策程序之評估-以全民健保醫療給付協議會議為例 / An Evaluation of Decision Procedure in Health Resource Priority Setting: The Payment Committee of NHI in Taiwan

蔡翔傑, Tsai, Hsiang-Chieh Unknown Date (has links)
全民健保醫療給付範圍的相關決策缺乏資訊公開性與參與性,引發許多醫療給付的糾紛案件,加上醫療資源有限,醫療需求隨國內人口平均餘命提升而增加,醫療資源優先配置的問題更顯其重要性。本研究建立一個合理的醫療資源優先配置決策程序評估架構,以改善目前國內資源優先配置決策程序,使用Daniels & Sabin(1997)所提出的「要求合理性的課則」(Accountability for Reasonableness)作為評估架構的主要構面,採用文獻分析法與層級分析法建構出一個完整的評估架構並且比較指標間的相互權重,接著使用深度訪談法試圖探索評估指標相對權重背後所代表的意涵。研究結果顯示醫事團體代表強調相關性與決策修正機會,政府代表則注重公開性與執行力,兩者對於醫療資源優先配置決策程序的期待有相當大的落差。基於研究發現,本研究主張應該增加協商機會以減少決策成員間的認知落差,帶動社會大眾對於資源優先配置的認識與參與,並針對目前決策程序的公開性、相關性、決策修正機會與執行力進行改善。 / The lack of information publicity and participation in the payment system of National Health Insurance (NHI) in Taiwan has been a critical issue. Besides numerous insurance payment disputations, the limited health resources and increasing health demand all call for an immediate solution to the problem of health resource priority setting in NHI.. This study aims to establish a systemic evaluative framework to improve on the health resources priority settings. In answer to the need, analytical hierarchy process and in-depth interviews have been conducted to develop a framework based on Accountability for Reasonableness. Qualitative and quantitative analysis of the surveys indicate some criteria and the meaning of the relative weight of each criterion. The results show a discrepancy between the governmental representatives and the healthcare organization ones on the expectation of health resources priority settings. The former focus on relevance, revision and appeals while the latter emphasize publicity and enforcement. According to the findings, this study suggests that an increase of negotiation is necessary to eliminate the discrepancy between the two groups. The government also need to introduce the public the idea of health resources priority settings and to modify the current procedure based on the four factors in Accountability for Reasonableness.
102

半導體產業供應鏈網路資源分配模式之研究 / The Model of Resources Allocation in Supply Chain Network for Semiconductor Industry

徐豐祺, Hsu, Feng-Chi Unknown Date (has links)
半導體生產的流程可分成四階段:晶圓生產(fabrication)、測試分類(sorting)、封裝(assembly)與檢驗(testing)。每個階段都有不同的廠商可提供服務。當晶圓生產廠商接獲訂單,其供應鍊管理者會根據產能、需求量、交貨日、技術水準與成本等考慮因素,決定此訂單應由何晶圓廠區生產、由何測試分類廠做分類、由何封裝廠做封裝與最後由何檢驗廠做檢驗。本研究的主要目的為在各種限制條件下,以最小成本為目標,找出完成客戶訂單的最佳廠商組合。可能的限制包括產能限制、交貨日的滿足、各廠區的技術水準及需求量的大小。本問題可視為產品組合、廠商組合與生產排程的綜合問題,過去常用的解決方法為整數與線性規劃的混合應用,但是由於牽涉的因素太多,常常問題的模式中變數與限制式過多導致無法解決。本研究先以資料的收集與模式的建構為主,利用並修改現有的產品結構樹模型使其變成供應鏈網路模式,並加入半導體產業供應鏈相關特性,建立一個以時間軸為機制的混合整數線性模式。並且以時間成本的概念來衡量整個半導體供應鏈的效能。 混合整數線性模式常會面臨許多問題,由於模式的複雜,變數與限制式過多,造成求解的困難。對電腦資源的需求很大,花費的時間也很長。同時對於問題的規模亦造成制限。於是本研究藉著修改Kim (1995) 的 backward list scheduling 演算法概念,建構一個解決問題的啟發式演算法,可快速求得一組近似最佳解之可行解。 由於供應鏈所面對的是隨機環境,因此必須以模擬的方式對上述模型進行檢驗,確認其有效性及適用的範圍。利用系統模擬方法,確定隨機變數與其分配,以建立模擬模型程式。實際進行模擬,以驗證上述供鏈模型之有效性,並瞭解、分析模型之適用性及應用方式。 對於半導體產業供應鏈廠商指派與資源分配之網路管理方面,提供一數量化的思考邏輯。運用數量化的模式表現出不同的半導體產業供應鏈廠商指派與資源分配之網路管理的問題,並提出解決問題的演算機制。
103

一般帳戶投資型年金之資產負債管理:免疫理論與最適資產配置之應用

謝冠生 Unknown Date (has links)
本研究主要是針對投資型年金之資產負債管理作探討,其中是就規避利率風險對於資產負債管理上的影響以及分析資產配置最適化作為研究的架構,而所利用的研究方法乃是取決於建構利率隨機模型並輔以免疫理論與Markowitz投資組合理論,以期在規避利率風險的同時,亦能將資產配置達至最佳化。 首先,為實際模擬出符合現實經濟環境變動下的隨機利率期間模型,本研究利用C.I.R利率期間結構模型來建構年金保單期間的利率結構,並且由於投資型年金之保單價值的累積特性,因此本研究同時亦建構出連接保單價值的投資資產之報酬率型態,進而模擬出各期之現金流量以及各項投資資產的存續期間;再者,藉由Markowitz投資組合理論,以在免疫條件之限制下進行最適資產配置之評估。 最後,以某知名的保險公司所推出的投資型年金商品作為本研究之實證對象,透過模擬之方法,將研究模型中之各項參數予以評估,並且根據上述之研究過程將免疫理論與投資組合理論相連接,以檢視投資型年金商品在規避利率風險的狀態下,其最適之資產配置比例是否與現行法令之規範相牴觸,而能給予適時之建議。另外,由本實證結果可知,經由本研究的分析流程,可以有效地給予年金管理者規劃出年金資產負債管理時的最適投資組合比例,並且在增加外國投資資產時,更能有效的增加年金資產之報酬,同時也不影響保險法對於投資資產的比例與總金額之限制。再者,對於探討規避利率風險前後之資產組合之資產報酬之變化時,可以進一步了解到,當年金管理者在運用免疫策略來規避利率風險時,其所面對的風險成本之多寡,以作為制定避險決策時的依據。 / This research explores the asset-liability management (ALM) for the Investment-Link-Annuity. Two aspects investigated in this research are the interest rate risk and the optimal asset allocation. Moreover, the major issue investigated here is the trade-off between the optimal investment return and the hedge of interest rate risk. We refer this trade-off as ALM cost. By using stochastic interest rate model, Immunization theory and Portfolio Selection Model, we construct an ALM model to achieve the optimal asset allocation given on hedging the interest rate risk under the immunization strategies for the insurance company. First, we utilize the public trading data for investment market in Taiwan and in USA from 1985 to 2000 and the investment-link annuity product of a well-know insurance company in Taiwan to simulate the cash flow and demonstrate the implementation of our model. By analyzing different simulations under various scenarios, the empirical results are as the followings: 1.The ALM cost for immunization strategies is very small, and is estimated to be about 1% to 2%. Therefore, we suggest that insurance companies should start to undertake the asset liability management as soon as possible. 2.If relaxing the investment restrictions of Insurance Law or allowing insurance company to invest in foreign investment market, the overall investment return will be increased and the ALM cost will be reduced effectively.
104

限制下方風險的資產配置 / Controlling Downside Risk in Asset Allocation

簡佳至, Chien, Chia-Chih Unknown Date (has links)
由於許多資產報酬率的分配呈現厚尾的現象,因此,本文探討將最低報酬要求限制條件加入傳統的平均數╱變異數模型中,考慮在分配已知的情形下,假設資產報酬率的分配為t分配及常態分配,來求取最適的資產配置;在分配未知的情形下,利用古典Bootstrap法、移動區塊Bootstrap法及定態Bootstrap法的抽樣方法來模擬資產報酬率的分配形式,並利用模擬的資產報酬率分配求出最適的資產配置。 同時,本文亦探討資產配置在風險管理上的運用,當分配已知時,若對分配參數的估計正確,則使用的最低要求報酬率就是此資產配置的涉險值,反之,若對參數的估計錯誤時,會對資產配置產生很大的影響及風險管理上的不正確;當分配未知時,利用模擬方法來產生分配,則使用的最低要求報酬率可看成是此資產配置的涉險值。 實證部分選取資料分成本國及全球,研究發現對於何種分配或模擬方法的資產配置績效最好?沒有一定的結論。其原因是各種分配或模擬方法皆必須視資料的性質而定,因此,本論文的貢獻僅在建議使用厚尾分配及利用模擬方法,來符合資產報酬率呈現厚尾的現象,並利用此分配,以期在考慮最低報酬要求限制條件下的資產配置更為精確。 / The distributions of many asset returns tend to be fat-tail. This paper attempts to add the shortfall constraint in Mean-Variance Analysis. When the distribution is known, we find the optimal asset allocation under student-t distribution and normal distribution. On the other hand, we use Classical Bootstrap, Moving Block Bootstrap, and Stationary Bootstrap to stimulate the distribution of asset return, and to obtain the optimal asset allocation. We also examine the risk management of asset allocation. When we use the correct estimators of parameters under the known distribution, the threshold in shortfall constraint is the value-at-risk in asset allocation. Otherwise, if using the wrong estimators, we get the incorrect asset allocation and the improper risk management. When the distribution is unknown, using simulation to generate the distribution, the value-at-risk is the threshold. The empirical study is conducted in two parts, domestic and global asset allocation. The results cannot point out which distributions and simulations are suitable. They depend on the data’s property. The contribution of this paper is to introduce some methods to fit the fat-tail behavior of asset return in asset allocation.
105

資產配置之動態規劃 / An Application of Dynamic Asset Allocation: Two-period Investigation

蔡秉寰, Tsai, Ping-Huan Unknown Date (has links)
資產配置乃是將資金分散投資到主要的資產類別中,諸如股票、債券、現金等。傳統的均數/變異數方法在資產配置上早已被廣泛的運用。但是,現今的金融情勢多變,多期配置的需求提高,傳統均數/變異數方法只處理單一期間的資產配置,且反應未來的能力不佳,顯然已經不適用。 本論文提供一種多期動態的資產配置,可以改良過去單點估計值的缺點,同時能夠將未來情境納入考量,使多期資產配置更富策略性。並實證在兩期的情況下,期中調整資產組合與不調整的差異性。從而瞭解持續的動態規劃,方能提升資產配置的效率性。 / Asset allocation is the process of dividing an investment fund among major asset classes such as equities, bonds, cash, etc. Traditional mean-variance portfolio selection is widely used for asset allocation. However, as time goes by, the financial condition changes rapidly. The method of mean-variance analysis has some limitations. It not only can’t deal with multiperiod asset allocation, but also cannot reflect future economic circumstances, especially for long-term investments. This research tries to use the method of multi-stage dynamic programming for asset allocation. This method can improve the pits of single estimate in using mean-variance analysis, and take future scenarios into account so that the model will become more useful in practice. The two-period empirical results have shown that using continuous dynamic programming to build strategic asset allocation decision can improve the efficiency of asset allocation.
106

連續時間模型下退休基金最適策略之研究

陳絳珠 Unknown Date (has links)
本研究針對退休基金管理的兩項重要議題:提撥政策與資產配置作最適規劃之探討。由於傳統退休基金的評價僅考慮單一期間的離散時間模型,不若多期規劃的效率性,因此,本研究考量連續時間下,利用控制理論觀點,將提撥金額與資產配置視為可調節的因子,以風險最小化為最適定義,提供基金多期管理的有效方法。 首先,為充分反映退休基金管理時所面臨的不確定因素,本研究假設資產價值服從幾何布朗運動,並且經由隨機微分方程式描述退休基金所累積資產與應計負債的動態隨機性質。其次,考量基金管理所面臨的提撥風險與清償風險,給定能夠量化這些風險的評估測度,藉以監督退休基金於管理期間的經營績效,並且利用Bellman方程式求出最適的基金提撥與資產配置策略。 最後以勞動基準法規範下的企業退休金計劃為實證對象,透過動態模擬估計模型中之參數,並且利用數值方法求出所需的函數值,將控制理論與情境模擬連結,藉以檢視現行固定給付退休基金之最適策略。由實證結果可知,透過本研究的方法的確可以有效管理基金同時符合財務清償能力的要求。利用動態規劃所得的最適策略與給定的風險評估函數相關,因此,基金決策者可以依據基金的特性給定適當的風險評估函數,依照不同的投資期限擬定合適的基金策略。 / This study explores two critical issues in pension fund management: funding policy and asset allocation. The traditional valuation of pension fund is restricted in one-period setting under discrete-time framework, and it is not efficient comparing to the continuous-time models. Therefore, in this study, control theory is employed to obtain the optimal strategy based on a specific plan dynamics. Employer's contributions and investment proportions are treated as the controllers in our model. Optimal solutions are obtained by minimizing the given risk performance in monitoring the multi-period fund management. First, the stochastic differential equations are constructed to describe the dynamics of the funding levels and the accrued liabilities. Geometric Brownian motions are used to model the assets held by the fund manager. Secondly, a stochastic control model with given risk measurement is formulated in a continuous-time framework to investigate the optimal decisions. In our approach, the plan's normal costs and accrued liabilities are simulated through plausible scenarios while the optimal contribution and asset allocation are solved through Bellman equation. At last, a specific pension scheme under the regulation of the Taiwan labor standards law is studied for numerical illustrations. A monitoring mechanism linking plausible scenarios and the closed-form solutions are employed to scrutinize the funding policy and asset allocation. The optimal strategies are estimated through dynamic programming under realistic workforce scenario. According to the result, it shows that the methodology in this study can assist the fund manager in obtaining the plan's financial soundness. Meanwhile, the optimal strategy can fully incorporate the given risk measurement. Hence, the policy maker can input certain managerial considerations into the performance measure to investigate the stability and solvency issues.
107

新產品發展過程之資源配置與績效之關係--以我國製造業為例 / The relation between resources allocation of NPD process and performance--for Taiwan manufacturing firms

鍾志明, Chung, Chih-ming Unknown Date (has links)
Takeuchi與Nonaka (1986)的研究指出,新產品對利潤的貢獻由七十年代的四分之一提升至八十年代的三分之一;Haas(1989)則指出,在美國的製造業中,有40%的營收來自新產品的銷售,32%的利潤亦來自於新產品的貢獻新產品對利潤的貢獻;而國內相關研究也有類似的結果。雖然新產品的開發上市對公司的貢獻如此大,但相對上,新產品的失敗率也相當高;Booz,Allen 與 Hamilton(1982)估計消費品失敗率約30%,工業品約為40%;Edgett等(1992)調查在英國的本土與日本廠商,發現英國廠商的新產品失敗率為45.7%,日本為40.2%,並認為產品的失敗率三十年來沒有明顯的改善,若從創意的產生到上市評估,則失敗率更高(須滕文德,民80)。新產品發展過程之管理為新產品成功的重要因素之一,但過去文獻多僅及於新產品發展過程之完整性,對於新產品發展過程之資源配置的研究較少,影響資源配置型態之因素為何?以及資源配置型態與新產品發展績效之關係為何?此關係又將受那些情境因素影響?即為本研究的主要動機。 經由文獻探討後,本研究將影響新產品發展過程資源配置之因素分為四大類:產品的創新性、新產品策略、組織規模、環境因素。除研究新產品發展過程資源配置之影響因素外,綜合其他學者之研究,發現資源配置與新產品之績效有顯著的關係存在,故本研究亦將延續此一主軸,更進一步發掘資源配置與各影響因素之配合對新產品發展績效之衝擊。 由於本研究所研究之部份主題牽涉公司之商業機密,且資源投入之衡量需由相當經驗之主管人員填答,因此本研究將採用便利抽樣之方式,尋求有意願配合之廠商,進行本研究之問卷調查。總計發出348份問卷(包括郵寄與親自發放),實際回收167份問卷,去除資料填答不全之無效問卷35份,實際有效問卷為132份,回收率為38%。 本研究以新產品發展過程之資源配置的結果進行分群,經由集群分析後,可區分為三種不同的資源負荷集群:「市場資源負荷型」、「技術資源負荷型」、「製造資源負荷型」。然後再以因素分析,從新產品策略、組織資源及環境因素此三大類可能影響因素、19題問項中,萃取出7個因素,再分析此七因素及產品創新性之影響。 研究發現,影響新產品發展過程之資源配置型態的因素則包括:「產品創新性」、「市場需求的成長與規模」、「新產品策略」、「產品特性」、「可用研發資源」及「競爭優勢」。「組織資源」及「新產品開發成本」對資源配置型態並無顯著影響。由此結果可發現,組織資源的多寡並非資源配置決策者所考慮的主要因素之一,反而應該是組織資源的配置決策過程或決策的組織等組織特質較有可能影響資源的配置。 本研究以資源配置型態為自變數,以整體績效為應變數進行分析,結果發現「市場資源配置」型態的新產品發展績效明顯高於「製造資源配置」,而「技術資源配置」型態的新產品發展績效則介於其中,檢定結果並不顯著。而此一關係又受到下列情境因素的影響:「產品創新性」、「產品特性」、「競爭優勢」及「新產品開發成本」。 第一章 緒論……………………………………………………...……1 第一節 研究背景與動機……………………………………….……1 第二節 研究目的……………………………………………….……5 第三節 研究前題與研究範圍………………………………….……7 第四節 研究限制……………………………………………….……9 第二章 文獻探討………………………………………………...…..11 第一節 新產品之定義………………………………………….…..12 第二節 新產品發展過程……………………………………….…..17 第三節 新產品發展過程資源配置………………………………..30 第四節 新產品發展績效……………………………….…………..37 第五節 新產品策略……………………………….………………..42 第六節 影響新產品發展過程之資源配置因素……………….…..46 第三章 研究設計……………………………….……………….…..53 第一節 研究架構……………………………….…………………..53 第二節 變數定義、變數衡量與問卷設計…………………….…..55 第三節 研究假設……………………………….…………………..65 第四節 研究對象與資料分析方法………………………………..72 第四章 研究發現--影響新產品發展過程資源配置之因素………..76 第一節 回收問卷基本資料分析……………………………….…..76 第二節 問卷之信度與效度分析……………………………….…..79 第三節 新產品發展過程資源配置型態…………………………..81 第四節 影響新產品發展過程資源配置因素之分析………….…..85 第五節 新產品發展過程資源配置型態與影響因素之關係….…..91 第五章 研究發現--資源配置型態與發展績效之關係……………106 第一節 資源配置型態與發展績效之關係…………………….…107 第二節 影響資源配置與新產品發展績效關係之因素……….…109 第六章 結論與建議……………………………….……………..…119 第一節 研究發現……………………………….…………………119 第二節 理論與實務涵意……………………………….…………129 第三節 對後續研究之建議……………………………….………132 參考文獻……………………………….…………………………..…135 附錄一 問卷……………………………….……………………..…148 附錄二 個案……………………………….……………………..…153 附錄三 附表……………………………….……………………..…166 / The contribution of new product is more and more important for the growth of company today, but the rate of failure of new products is at least 30% (Booz, Allen and Hamilton, 1982; Edgett et al., 1992). There-fore, the management of new product development (NPD) process must be devoted more attention. There were many researches discussing NPD process, but it's hard to find out the researches regarding the resources allocation of NPD process. Resources allocation is a important part of implementation of new product strategy. This study identifies three type of resources allocation of NPD process: Market-resources-load, Tech-nology-resources-load, Manufacturing-resources-load. In addition, the factors influencing the choice of the type of resources allocation includes: the degree of innovation of new product, the growth and the size of market demand, new product strategy, features of new product, available R&D resources, relative competitive advantage. According to the evaluation of respondents, the performance of Market-resources-load resources allocation is better than others, but this relation is contingent under different situations such as the degree of innovation of new product, features of new product, relative competitive advantage, the cost of developing new product.
108

開放新銀行設立對舊銀行經營效率的影響

鍾怡如, Chung, Yi-Ru Unknown Date (has links)
本研究以民國75至86年間,新銀行開放設立前已存在之本國舊銀行實際經營資料,利用資料包絡分析法估計成本效率值,並將之分解為純技術效率、規模效率及配置效率。再利用Tobit迴歸分析,以探討開放新銀行設立對本國舊銀行經營效率之影響。 研究結果發現,整體舊銀行投入資源之運用效率,仍有很大的改善空間。此外,成本無效率之來源主要為技術無效率。 考慮其他影響效率之因素後,開放新銀行設立對舊銀行之經營效率具有顯著之正向影響。此結果顯示新銀行設立對舊銀行之經營形成很大的競爭壓力,導致本國舊銀行不論在資源投入、規模調整或資源配置上,皆積極努力地改善。本實證結果與政府希望透過開放新銀行,對經營僵化之國內銀行業加以刺激,以提升舊銀行經營效率之目標相一致。 / This study empirically examines whether opening up the new banks to establish affects various efficiency ratios of Taiwan old banks or not. It uses Data Envelopment Analysis (DEA) to assess cost efficiency, pure technical efficiency, scale efficiency and allocative efficiency based on the Taiwan old banks data from 1986 to 1997. Then, applies the Tobit censored regression model to examine the relationship between opening up the new banks to set up and these efficiency measures. The empirical result shows that the usage efficiency of resource inpute of whole old banks isn't up to the appropriate point, so there is plenty of space for improvement. Besides, cost inefficiency primarily results from technical inefficiency, not allocative inefficiency. After considering other factors of the effects of efficiency, it's obviously positive relationship between opening up the new banks to set up and operating efficiency of old banks. The result shows that these new banks establish put competitive stress on the operation of old banks. So those old banks try hard to improve their resource input, scale adjustment, or resource allocation, etc. This result corresponds with the government's intention to raise the operating efficiency of original banks.
109

台灣銀髮族資產持有行為之探討 / The assets-holding of Taiwanese elders

張日青 Unknown Date (has links)
我們利用「台灣地區中老年身心社會生活狀況長期追蹤調查研究」這份資料,以似無關迴歸(Seemingly Unrelated Regression)模型,探討老人的資產持有行為,發現:一般老年人口並不偏好持有股票,持有行為相當少見,但高教育、高所得、都市化地區(尤其是直轄市)的老人,可能分別因為高教育程度、所得效果影響、都市地區資訊流通快速等因素,使得這類型老人明顯較願意持有股票。 另一方面,在台灣,不動產扮演的角色特殊,傳統認為其與家族宗系連結,在持有行為上並非只從風險報酬觀點去看待,通常還與其他考量有關,因此在持有行為上有其特殊模式。 同時,我們也發現,老人婚姻關係的消解(dissolution),例如離婚/分居,將對資產持有產生負面的財富效果影響,使得這類型老人各項資產的持有都顯著低於已婚/同居的老人;而健康情形越差的老人持有的不動產與存款也越少,應與此類老人有較高的醫療與保健支出,造成負面的財富效果有關。 除此之外,台灣老人平均而言,持有的不動產會隨年紀降低,但持有的存款會隨年紀而上升,主要與台灣老人隨著年紀上升,所得逐漸不足以維生,產生了反儲蓄(dissave)不動產的現象,有所關聯。我們認為台灣確實存在老人「以房養老」的現象。 最後,我們認為很重要的一點是,台灣老人資產的持有行為,並不是使用傳統的風險報酬概念就能解釋,我們必須考量其他可能因素,才能有效分析台灣老人所表現出來的資產持有行為。 / The general elders don’t prefer to hold stocks, but the elders of high-level education, the elders of high-level income and the elders in metropolis are more willing to hold stocks. Besides, the real estate plays a special role. People regard that it is linked up with the family or kindred. We also find out that the dissolution of relationship in elder’s marriage causes negative wealth effect on holding assets. The similar effect exists in much unhealthy elders. The elders hold less real estate as they getting older, but hold more stocks. It might due to that elders dissave their real estate. Finally, besides perspective of risk-reward, it might appropriate that think the behavior of holding assets in other view-points.
110

動態規劃數值解 :退休後資產配置 / Dynamic programming numerical solution: post retirement asset allocation

蔡明諺, Tsai, Ming Yen Unknown Date (has links)
動態規劃的問題並不一定都存在封閉解(closed form solution),即使存在,其過程往往也相當繁雜。本研究擬以 Gerrard & Haberman (2004) 的模型為基礎,並使用逼近動態規劃理論解的數值方法來求解,此方法參考自黃迪揚(2009),其研究探討在有無封閉解的動態規劃下,使用此數值方法求解可以得到 逼近解。本篇嘗試延伸其方法,針對不同類型的限制,做更多不同的變化。Gerrard & Haberman (2004)推導出退休後投資於風險性資產與無風險性資產之最適投資策略封閉解, 本研究欲將模型投資之兩資產衍生至三資產,分別投資在高風險資產、中風險資產與無風險資產,實際市場狀況下禁止買空賣空的情況與風險趨避程度限制資產投資比例所造成的影響。並探討兩資產與三資產下的投資結果,並加入不同的目標函數:使用控制變異數的限制式來降低破產機率、控制帳戶差異部位讓投資更具效率性。雖然加入這些限制式會導致目標函 數過於複雜,但是用此數值方法還是可以得出逼近解。 / Dynamic Programming’s solution is not always a closed form. If it do exist, the solution of progress may be too complicated. Our research is based on the investing model in Gerrard & Haberman (2004), using the numerical solution by Huang (2009) to solve the dynamic programming problem. In his research, he found out that whether dynamic programming problem has the closed form, using the numerical solution to solve the problems, which could get similar result. So in our research, we try to use this solution to solve more complicate problems. Gerrard & Haberman (2004) derived the closed form solution of optimal investing strategy in post retirement investment plan, investing in risky asset and riskless asset. In this research we try to invest in three assets, investing in high risk asset, middle risk asset and riskless asset. Forbidden short buying and short selling, how risk attitude affect investment behavior in risky asset and riskless asset. We also observe the numerical result of 2 asset and 3 asset, using different objective functions : using variance control to avoid ruin risk, consideration the distance between objective account and actual account to improve investment effective. Although using these restricts may increase the complication of objective functions, but we can use this numerical solution to get the approximating solution.

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