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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.
1

類神經網路與基因演算法在投資策略上的應用 / The application of artificial neural network and genetic algorithm on investment strategy

戴維志 Unknown Date (has links)
近年來,在財務領域中,有越來越多的人想藉助人工智慧系統來幫助我們做預測與處理最佳化的問題,而類神經網路與基因演算法為兩種最常見的處理系統,可幫助我們監控與做出適當的決策。而本文特別針對以上兩種系統,分別在不同的領域中,做出適當的應用。 在類神經網路方面,本文試圖結合配對交易來建構出一套能獲利的交易模式。由於在配對交易的部分,進出場時機的門檻值是影響獲利的一大重要關鍵,因此若能利用類神經網路輔佐我們的交易並預測適當的進出場時機,或許可提高我們的交易績效與報酬。 而在基因演算法的部分,由於此演算法的最主要功能是處理最佳化問題,因此本文試圖用基因演算法建構最佳化的投資組合,結果指出,利用此方法所得之投資組合在單位風險值的衡量之下,有較好的報酬表現。
2

確定提撥制下之最適投資決策:隨機最佳化之模型建構

林士儼 Unknown Date (has links)
現行退休金制度已由確定給付制轉換為確定提撥制。投資風險從雇主的身上移往至員工身上,員工退休基金的金額也不確定。因此為了降低投資風險本研究採用預定的所得替代率作為目標給付,並藉由模擬最佳化的方式探討在不同模型假設下之最適資產配置。   本文中最佳化的方式是使用基因演算法,以避免以往演算法最佳化過程中掉入非最佳解的窘境。我們得到以下結論:(一) 靜態資產配置隨投資組合不同報酬率以及變異有很大的差異。即使在相同投資組合下,Regular Rebalance 與 Buy & Hold導致不一樣的結果。(二)動態投資組合較靜態投資組合能獲得高報酬與低風險投資績效。(三) 不同風險偏好投資人可以尋找其最佳化之動態資產配置。
3

以基因演算法探討國際投資組合策略之研究

李卿企 Unknown Date (has links)
資訊的發達,加快了經濟自由化的腳步,所以國際投資的機會也日漸增加,所以,如何利用國際投資組合來分散國內無法分散的系統風險,增加投資報酬率,以成為日漸重要的課題。 本研究試圖以基因演算法在不同的投資策略下追求各國最適的投資比率,基因演算法是一模擬生物演化過程而發展出的一追求最適解的方法,對目標函數的設定沒有太多的限制,在基因演算法下對投資策略的設定將更具有彈性。 在基因演算法下,本研究以亞太地區九個國家的股價指數為投資標的物,設定七個投資策略,其動機主要可分為二,一為欲追求較高的單位風險投資報酬率,二為欲有效模擬新興國家指數,分別比較其樣本期間內外的單位風險報酬率、一致性、持股穩定性與模擬能力,並試圖操縱不同的模擬期間長度,比較其差異性。 實證結果顯示,如果投資者欲追求較高的單位風險投資報酬率,可能應該注重投資組合風險之管理,追求投資組合風險最小化將可獲得投資組合在樣本期間外的單位風險報酬最高且在該投資策略下具持股穩定性,所以手續費的變動對其表現績效的影響不大。若投資者欲有效模擬新興國家指數則應使樣本期間內的模擬股價報酬率與新興國家指數報酬率的相關係數最大,本研究模擬的最高相關係數只有76.07%,在未來仍須繼續努力對目標函數加以改進。 本研究僅就模擬期間12週與34週加以比較,結果發現模擬期間12週的表現績效優於24週的表現績效,但模擬能力較差,這是否告訴我們較短的模擬期間將可使樣本期間外的表現績效更為優秀,將需做更進一步的確認。 本研究亦針對同一目標函數以基因演算法與傳統的二次歸劃法加以比較,結果在樣本期間外的表現績效、持股穩定性與模擬新興國家指數的能力上,基因演算法似乎都較優於傳統的二次歸劃法。
4

Implied Volatility Function - Genetic Algorithm Approach

沈昱昌 Unknown Date (has links)
本文主要探討基因演算法(genetic algorithms)與S&P500指數選擇權為研究對象,利用基因演算法的模型來估測選擇權的隱含波動度後,進而求出選擇權的最適價值,用此來比較過去文獻中利用Jump-Diffusion Model、Stochastic Volatility Model與Local Volatility Model來估算選擇權的隱含波動度,使原始BS model中隱含波動度之估測更趨完善。在此篇論文中,以基因演算法求估的選擇權波動度以0.052的平均誤差值優於以Jump-Diffusion Model、Stochastic Volatility Model與Local Volatility Model求出之平均誤差值0.308,因此基因演算法確實可應用於選擇權波動度之求估。 / In this paper a different approach to the BS Model is proposed, by using genetic algorithms a non-parametric procedure for capturing the volatility smile and assess the stability of it. Applying genetic algorithm to this important issue in option pricing illustrates the strengths of our approach. Volatility forecasting is an appropriate task in which to highlight the characteristics of genetic algorithms as it is an important problem with well-accepted benchmark solutions, the models mention in the previous literatures mentioned above. Genetic algorithms have the ability to detect patterns in the conditional mean on both time and stock depend volatility. In addition, the stability test of the genetic algorithm approach will also be accessed. We evaluate the stability of the new approach by examining how well it predicts future option prices. We estimate the volatility function based on the cross-section of reported option prices one week, and then we examine the price deviations from theoretical values one week later.
5

Risk Preference, Forecasting Accuracy and Survival Dynamics:Simulations Based on a Multi-Asset Agent-Based Artificial Stock Market / 風險偏好與預測能力對於市場生存力的重要性

黃雅琪, Huang, Ya-Chi Unknown Date (has links)
風險偏好與預測精確性對生存力的重要性吸引進來許多理論學者的注意。一個極端是認為風險偏好完全不重要,唯一重要是預測精確性。然而此乃基於柏拉圖最適配置之下。透過代理人基模型,我們發現相異的結果,即風險偏好在生存力上扮演重要角色。 / The relevance of risk preference and forecasting accuracy to the survival of investors is an issue that has recently attracted a number of recent theoretical studies. At one extreme, it has been shown that risk preference can be entirely irrelevant, and that in the long run what distinguishes the agents who survive from those who vanish is just their forecasting accuracy. Being in line with the market selection hypothesis, this theoretical result is, however, established mainly on the basis of Pareto optimal allocation. By using agent-based computational modeling, this dissertation extends the existing studies to an economy where adaptive behaviors are autonomous and complex heterogeneous, and where the economy is notorious for its likely persistent deviation from Pareto optimality. Specifically, a computational multiasset artificial stock market corresponding to Blume and Easley (1992) and Sandroni (2000) is constructed and studied. Through simulation, we present results that contradict the market selection hypothesis. Risk preference plays a key role in survivability. And agents who have superior forecasting accuracy may be driven out just because of their risk preference. Nevertheless, when all the agents are with the same preference, the wealth share is positively correlated to forecasting accuracy, and the market selection hypothesis is sustained, at least in a weak sense.
6

應用基因演算法重劃選區 / Electoral Redistricting In Genetic Algorithm

李俊瑩 Unknown Date (has links)
為因應選舉法規變更或時代變遷,往往必須重劃選區。傳統上,選區重劃都是以人工方式劃分。以人工方式劃分選區固然能考慮較多因素,包括最難數據化的人文因素,但人力成本高,也容易引起爭議。 本研究中,我們提出一個有系統的方式以自動劃分選區。主要的考慮因素為選區之人口數、選區形狀及二級行政區之完整性。我們的劃分方式主要分為三部份:產生起始選區、二級行政區分割修正及選區形狀調整。在產生起始選區步驟,我們根據位能場的觀念,劃分出人口數符合標準之起始選區,再經過行政區分割修正以維持二級行政區之完整性,最後採用基因演算法來調整選區形狀,以避免傑利蠑螈的狀況。 我們以台北市為例,來闡述我們的方法,實做的結果顯示我們的方法能有效的做正確的選區重劃。 / Electoral redistricting is normally required when election regulations changed. Traditionally, electoral redistricting is done manually. Though manual redistricting could consider humane or cultural factor, which may be very difficult to be included in the computation model, the cost of manual redistricting normally is high. In addition, manual redistricting may induce controversial issues. In this thesis, we propose a systematic way that could do the electoral redistricting automatically. Our major considerations are: (1) the population must be evenly partitioned, within an acceptable error; (2) the shape of the redistricted region is reasonably good; (3) the integrity of the second level district must be kept reasonably well. Our method consists of three major parts: initial district production, district’s integrity fixing, and district reshaping. The concept of potential is used in producing the initial districts. A heuristic is used in fixing the district’s integrity. And, finally, Genetic Algorithm is used in district reshaping. We use Taipei City as an example to illustrate our idea. Experimental results show that our method can do electoral redistricting effectively.
7

協同式數位內容設計服務市場 – 以語意為基礎之遺傳法優化模糊機構設計 / Semantic- Based Digital Content Design in Collaborative Service Marketplace

吳彥成, Wu,Yen Cheng Unknown Date (has links)
科技進步使人類生活不斷改善,產業的發展逐漸轉變,服務業的崛起已成為世界趨勢。在資訊科技的推動下,服務業除了關注人與人的互動與商業的交換之外,科技漸漸成為另一個重要因素,服務產業的核心轉為由科技、人、及商業流程所組成,新的科學理論─「服務科學」應運而生。服務科學的目的在整合各領域之知識以促進服務創新。另一方面,服務產業的重要成員─數位內容產業正迅速發展,在數位內容創作領域中,消費者與生產者角色逐漸模糊,成為協同互利的夥伴,這樣的轉變衍生許多新的問題有待解決,包括夥伴關係如何建立與平台機制的發展等。因此,透過服務科學解決數位內容產業的問題,當是一項值得採用之方法。本研究透過服務科學的三個面向─服務組成、服務流程、以及服務價值作為研究的背景架構,並採用結合語意網路、模糊規則、基因演算法所組成之語意式模糊基因演算法作為數位內容問題的解決方案,在電子市集的環境推動下,以協同式夥伴配對的方式,達到使用者的創作利益。系統共分三大服務組成:本體發展模組、語意式模糊基因演算夥伴配對模組、以及協同價值評價模組,以語意定義創作問題與產品的概念,並透過基因演算法改善模糊規則,釐清概念間的關係,最後透過市場機制完成配對達成雙方利益。本系統之預期貢獻分為:(1)利用服務科學改善數位內容問題。(2)為服務科學方法之應用提供發展方向。 / The economies of the world have been shifting labor from agriculture and manufacturing into services. In the emergent concept of service science, competition will center on value co-creation experiences with information technology and service innovation refers to invented service system designs yielding values to real service problems. This paper presents a novel service system design for the digital content industry. This service design is unfolded with a marketplace featuring producers/consumers collaboratively co-creating digital contents and a self-regulating mechanism enabled by a semantic-based fuzzy genetic approach. In the marketplace, the roles of consumers and producers blur, and they are partners who collaborate to attain mutual benefits. The service system encompasses three service components (ontology developer, S-FGA partnership matcher and co-created value appraiser) that altogether work to empower producers/consumers who can effectively co-create their digital contents in a novel collaborative way. In addition to presenting a solution to digital content creation, this paper also showcases a new methodology for service innovation referred in service science.
8

基於Hadoop雲端運算架構建立策略交易與回測模擬平台 / Building algorithmic trading and back-testing platform based on Hadoop

黃柏翰 Unknown Date (has links)
為了讓一般的投資大眾能享有智慧型、系統化的策略交易環境,本研究計畫發展一個可供大量使用者共用、並且容易上手的策略交易平台。為了達到這個目的,此平台必須擁有快速且大量的運算能力,雲端運算所提供之大量且可擴充的運算能力,使之成為最適宜的平台。為滿足不同使用者不同的投資偏好,此平台提供多項常用之技術指標與K線型態辨識功能讓使用者利用基因演算法產生符合其偏好的交易策略。在策略產生之後,使用者可以在平台上檢視交易策略在不同商品、不同時間區間上的表現,並從最後的策略回測報告中加以評估,挑選出獲利能力、波動程度與交易頻率都符合需求的交易策略。
9

基於基因演算法發展之最佳化合作學習分組策略:以問題導向學習為例 / Developing a Group Formation Scheme for Collaborative Learning : A Case Study on Problem-Based Learning

郭旗雄, Kuo, Chi Hsiung Unknown Date (has links)
本研究旨在探討基於基因演算法(genetic algorithm)在同時考量先備知識水平及學習角色異質互補,以及社會互動關係同質因素下,發展之最佳化問題導向網路合作學習分組策略,是否有助於提升問題導向網路合作學習之學習成效、互動關係、團體效能與團體凝聚力。 本研究採用準實驗研究法,以新北市某國小六年級三個不同班級合計83名學生為研究對象,並將三個班級學生隨機分派為採用基因演算法最佳化分組策略的實驗組,以及分別採用隨機分組及學生自行選擇分組策略的控制組一與控制組二,三組學習者皆在問題導向學習系統(Problem-based learning system,簡稱PBL)上進行不同分組策略之問題導向網路合作學習活動。藉由學習成效與團體效能與團體凝聚力評量,以及分析三組學習者在問題導向學習系統上的學習歷程與互動關係,最後再輔以半結構式訪談,以驗證三種不同分組策略在學習成效、互動關係、團體效能與團體凝聚力上的差異。 結果顯示本研究所提出之最佳化問題導向網路合作學習分組策略具有提升學習成效之效益;本研究所提出之最佳化分組策略對於促進問題導向網路合作學習之同儕互動具有正面效益;採用不同問題導向網路合作學習分組策略組別學習者在團體效能與團體凝聚力上具有顯著差異;採用最佳化分組策略組別學習者在問題導向網路合作學習的滿意度接近同意的水準。 / This study aims to explore whether the optimized group formation scheme based on genetic algorithm helps students enhance learning performance, interaction, collective efficacy, and group cohesion in collaborative problem-based learning environment. Factors associated with heterogeneous complementation of students’ prior knowledge levels and learning roles and the homogeneity of social interaction relationship were simultaneously considered in the genetic algorithm-based optimized group formation scheme. In this paper, a quasi-experimental research method is employed to assess the effects of three different group formation schemes on the learning performance, interaction, collective efficacy, and group cohesion in collaborative problem-based learning environment. Eighty-three students in three different sixth-grade classes in an elementary school in New Taipei City were invited to participant in the experiment and were randomly divided into three groups: the experimental group, which adopts genetic algorithm-based optimized group formation scheme, and two control groups, one is randomly grouped; while the other allows students group themselves. Learners in these three groups all use collaborative problem-based learning system (CPBL) to perform collaborative problem-based learning activities. Learning performance, interaction, group efficacy and group cohesion evaluation are applied to analyze the learning process and interaction among learners in these three groups. Finally, a semi-structured interview is supplemented to validate the variation of these three different group formation schemes in learning performance, interaction, group efficacy and cohesion. The result showed that the genetic algorithm-based optimized group formation scheme helps students promote learning performance and provides positive effects on peer interaction in collaborative problem-based learning. Three group learners adopting different group formation schemes for collaborative problem-based learning show significant difference on group effectiveness and group cohesion. The satisfaction of learners adopting genetic algorithm-based optimized group formation scheme for collaborative problem-based learning reached a nearly agreed standard.
10

電源轉換器外部零件參數最佳化設計之研究

郭昭貝 Unknown Date (has links)
為了提升競爭優勢與生產能力,並進而達到永續經營的目的,突破現況、持續改善產品品質、降低產品成本與服務成本則成為提昇競爭力的重要因素之一,因此產品在設計開發階段就必需要考量品質與成本的問題。 本研究以電源轉換器為對象。該電源轉換器目前已設計完成且已通過美國UL安規認證,並已在國內量產銷售,但因為該電源轉換器的溫升及其變異很大,仍然會導致該產品的壽命過短,因此降低電源轉換器的溫升及其變異是一急需解決的問題。 透過了田口與實驗設計的方法規劃及進行實驗並收集數據。並利用十二種分析方法(包括:田口方法、主成份分析、主成份+倒傳遞類神經網路+基因演算法、主成份灰關聯+倒傳遞類神經網路+基因演算法、指數型理想函數+倒傳遞類神經網路+基因演算法、MSE方法、MSE方法+倒傳遞類神經網路+基因演算法、SUM方法、SUM方法+倒傳遞類神經網路+基因演算法、重要零件加總法、重要零件加總法+倒傳遞類神經網路+基因演算法)對實驗數據進行分析,以決定最適因子水準組合。 由改善後的確認實驗得到:雖然平均溫升下降的程度不大,然而大部份量測點的溫升標準差都顯著變小了。因此本研究在降低該電源轉換器溫升變異的效果十分顯著。對於電源轉換器的生產者而言,品質提升就是提升銷售量的保證,因此本研究所得到的最適因子水準組合,雖然產品在成本上有些微的增加,但品質改善後之產品將可為生產者帶來更多有形與無形之利益。

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