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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.
71

退休基金的策略性資產配置-以勞退新制為例

蔡牧岐 Unknown Date (has links)
『勞工退休金條例』於民國94年7月1日施行後,我國的勞工退休金經營管理模式有了根本上的變化。原來舊的制度下,退休金是以確定給付的方式經營,而在新制下則是以確定提撥的模式營運。新制由於不必考慮負債面,其資產配置的自由度相對來說大幅提高。然而,為了滿足法規『投資報酬率不得低於兩年期定存利率』之限制、以及達成高所得替代率的理想,退休基金的管理者將面臨追求短期穩定、以及長期高報酬兩項互為抵換目標的困難抉擇。 如何用一套較為實務上可行的方法,為新制下的退休基金擬定一套合乎其投資目標的長期策略性資產配置,是本研究所關心的課題。本文採用的方法是以多元蒙地卡羅模擬法(Monte Carlo Simulation),依據實際的資本市場假設來模擬整個投資組合期望報酬率的機率分配,並根據結果分析各種配置的優劣、提供決策者做參考。 本研究建議新制下退休基金的理想資產配置區間為:美國股票30%~40%、國際股票20%~30%、固定收益證券20%~30%、不動產5%~15%、以及私募股權0%~10%。其中,由於退休基金在成立前期的流動性需求較低,可以配置較高的比重於股票和不動產;後期則為了定期支付退休金、可以提高固定收益證券的比重。然而,本研究發現:『提高固定收益證券比重所帶來的短期穩定之加分、將不如其所犧牲的長期高報酬之減分』,因此不建議退休基金的管理人太早提高固定收益證券的投資比重。 此外,透過情境分析與敏感性分析,本研究認為長期而言,不動產是最為穩定、且又能同時達成長期高報酬目標的最佳投資標的。至於在戰略性配置上,如果基金管理者預期未來市場可能會出現長期動盪,則應該降低私募股權的比重。
72

消費者視覺觀點與廣告訴求類型適配度之體現模擬與溝通效果 / The Effects of Embodied Simulation of Fit between Customers' Visual Perspectives and Advertising Appeals

董重麟 Unknown Date (has links)
本研究主要探討消費者想像視角與訊息相適配之說服效果。心像是指感官資訊在短期記憶中運作的心理歷程,在說服文獻中扮演著重要的角色。由過去文獻可知,個體在進行想像時,可以採取兩種不同的想像觀點,一個是行動者觀點,另一個是旁觀者觀點。兩種不同視覺觀點會提供不同的心像資訊,進而影響個體對所想像事件或行動的解讀。旁觀者觀點強調行為的個人意義及個性上的展現,而行動者觀點則強調情境所賦予的感覺及所喚起的情緒。視覺觀點在社會心理學中已有廣泛的研究,但尚未應用到行銷說服領域中。本研究藉由整合心像、視覺觀點、及體現模擬的相關文獻,提出一個觀念性的研究架構,試圖說明當消費對採用不同的視覺觀點時,是如何影響其對廣告訴求的偏好,且是藉由何種心理機制來中介視覺觀點與廣告訴求相一致的說服效果。 針對上述的研究目的,本論文設計三個研究來驗證視覺觀點與廣告訴求適配的說服效果。研究一主要是驗證,若消費者採用行動者觀點來想像,則偏好體驗型產品,相反的,若消費者採用旁觀者觀點來想像,則偏好象徵型產品。研究二主要驗證,若消費者採用行動者觀點來想像,則廠商的溝通策略應強調產品屬性的體驗性利益,相反的,若消費者採用旁觀者觀點來想像,當廠商的溝通策略應強調產品屬性的象徵性利益。研究三是植基體現模擬中預設用途的概念,主要探討的是,如何在廣告圖片中安排預設用途線索,進而可以激發不同的視覺觀點。特別的是,當廣告圖片中有互動的預設線索時,則可以激發出旁觀者觀點,此時應強調象徵型訴求,相反的,當廣告圖片中沒有互動的預設線索時,則可以激發出行動者觀點,此時應強調體驗型訴求。且由三個研究結果可知,視覺觀點與廣告訴求相適配所產生的較佳產品態度,是由體現模擬所中介的。 / The purpose of this research is to understand the persuasive impact of the fit between the visual perspectives and the advertising appeals. Mental imagery, the process by which sensory information is represented in working memory, plays a critical role in persuasion. From a review of the literature, we realize that events can be imagined through the first-person perspective or the third-person perspective. The adoption of the specific vantage point can determine the inference people make about an imagined situation. In particular, the third-person perspective results in a greater dispositional inference, and highlights the broader meaning of the imagined situation, whereas the first-person perspective discloses more information about the inner, affective components of the imagined situation. Visual perspectives have been studied extensively in social psychology, but its implication is rarely applied to consumer behavior. This study adopts three experiments to examine the persuasive impact of fit between the consumers’ visual perspectives and advertising appeals. Study One suggests that when consumers adopt the first-person visual perspective, compared to a symbolic product, consumers would prefer the experiential product; on the other hand, when consumers adopt a third-person visual perspective, compared to an experiential product, consumers would select the symbolic product. Study Two proposes that when consumers adopt the first-person visual perspective, manufacturers should emphasize a product’s symbolic benefits. On the contrary, when consumers adopt a third-person visual perspective, manufacturers should stress a product’s experiential benefits. Study Three demonstrates that affordance cues would prime different visual perspectives, and when the visual perspective and advertising appeals fit mutually, it will have a strong persuasive effect. In particular, when there is an affordance cue in an advertisement, it will encourage consumers to adopt the third-person visual perspective, and then prefer symbolic appeals. On the contrary, when an advertisement does not have any affordance cues, it will stimulate consumers to embrace the first-person visual perspective, and then prefer experiential appeals. All three studies demonstrate that when there is a fit between the visual perspectives and the advertising appeals, consumers will generate a fluent embodied simulation, which would lead them to have a positive product attitude and purchase intention. The results of these three studies not only enrich the literature of visual imagery and marketing communication but also provide useful advice to manufacturers, especially on how to create the fit between product positioning and advertising, in order to promote the the positive product attitude and purchase intention of customers.
73

結構型金融商品之評價與分析:連結一籃子商品之保本型票券 / Pricing the structured notes-capital protected note linked to a basket of commodities

曾瓊葦 Unknown Date (has links)
金融風暴過後,在預期全球景氣轉佳之下,將帶動原物料市場價格之走揚。故能源及基礎金屬商品等的投資需求增加,近年來也出現不少連結能源及商品的投資工具。加上現今低利率之經濟環境,使得投資人希望尋求有較市場利率高之獲利率的金融商品。 本論文採用市場上銷售的結構型商品來進行評價與分析,其為連結一籃子商品之保本型票券。本文以蒙地卡羅模擬法作產品之評價及分析,讓讀者充分瞭解產品結構、報酬型態與成本以及所面臨的風險;此外也從發行商的角度,並分析其可運用的避險策略。
74

固定給付制退休金之最佳控管:隨機模擬方法之應用

張乃懿, Chang, Nai Yi Unknown Date (has links)
本研究中以隨機模擬的方法應用於退休金最佳控制理論中,並將下跌風險(Downside Risks)加入二次最佳化函數中作為最適化準則,再以英國與美加地區不同提撥率模型做為研究對象,觀察不同情境下之結果。Haberman(1994)首先提出以最適化方法應用於固定給付制退休金基金上,並具體建立二次最適化準則,以提撥與資產的變異作為控制因子。Chang(2003)以下跌風險的觀念,指出退休金基金經營時管理人常較注意提撥過多與資產不足風險,若經營時考慮下跌風險,則會產生與原來考量不同之結果。本文以Chang(2003)之研究為基礎,將其建議之最佳化函數做為考量下跌風險之依據,並提出改良英國與美加地區之提撥率模型,採模擬的方式進行最佳化,探討其對不同提撥率模型之影響。研究結果發現若以隨機模擬作為最佳控制方法,在不同人口假設及精算模型下,會產生相同之結果,且發現下跌風險對於不同提撥率模型有不同之影響,其中建議的英式模型有效降低風險,而美式提撥率模型對於提撥率比例與資產負債比例在最佳化下有較理想之結果。最重要的,退休金基金管理人可利用隨機模擬的方式進行最佳化控制,以提供決策之參考依據。
75

市場模型下利率結構型商品之評價與分析

王靖雯 Unknown Date (has links)
在過去,不外乎藉由瞬間短期利率的隨機過程或瞬間遠期利率的隨機過程來描述利率期間結構,應用這些方式理論上雖然可行,但是市場上並無法觀察得知這些瞬間利率。1997由Brace、Gatarek及Musiela提出之LIBOR市場模型,直接推導市場上可觀察得到之LIBOR利率的隨機過程,因此不需如傳統評價模型尚須對利率做轉換,可以直接以市場上觀察到之LIBOR報價帶入模型中做評價。由於市場上有愈來愈多的利率衍生性商品,不是由單純的cap或是swaption來組成,因此很難求出封閉解,所以通常使用數值方法來解決評價的問題,常用的數值方法有樹狀圖評價法及蒙地卡羅模擬法,由於使用樹狀圖評價法必須對利率做假設,才能使項樹的節點重合不至於增加太多的運算困難;因此,本文選擇使用蒙地卡羅模擬法,透過機率測度的轉換,推導出符合商品設計的遠期LIBOR利率的動態過程,進而模擬出商品的價格,在LIBOR市場模型下使用蒙地卡羅模擬法的好處在於,只要了解商品的設計方式,針對不同商品尋找合適的遠期LIBOR利率動態過程,便可利用模擬的方式得到商品價格。
76

信用損失分配之尾端機率估計-同質法與拉普拉斯近似法之比較

蔡旻樺 Unknown Date (has links)
信用風險為金融業經營上最大的風險來源,也是金融業損失的最主要的原因,近日企業紛紛不約而同的強調風險控管的重要性,風險控管更被視為下一波的競爭力,信用風險更是佔銀行各項風險之首。 本文將著重信用風險損失機率分配之探討,然後針對兩種近似方法,同質性近似與拉普拉斯近似模式以及各種不同的投資組合,研究其與蒙地卡羅之配適情形,並嘗試利用比常態厚尾的t分配,目的是為了找出更加保守的估計方式。 分析結果顯示,每一種近似法都沒有絕對的好或壞,各有其相對帶來的效益,同質性近似法不需花費很長的時間,且其結果大致與蒙地卡羅模擬相符,相對來說,拉普拉斯近似法所需的時間較長,但是其對於估計很小之違約機率的準確性是非常有幫助的。整體而言,此二種估計法皆可提供風險管理者作為估計違約機率的參考。
77

維度縮減應用於蛋白質質譜儀資料 / Dimension Reduction on Protein Mass Spectrometry Data

黃靜文, Huang, Ching-Wen Unknown Date (has links)
本文應用攝護腺癌症蛋白質資料庫,是經由表面強化雷射解吸電離飛行質譜技術的血清蛋白質強度資料,藉此資料判斷受測者是否罹患癌症。此資料庫之受測者包含正常、良腫、癌初和癌末四種類別,其中包括兩筆資料,一筆為包含約48000個區間資料(變數)之原始資料,另一筆為經由人工變數篩選後,僅剩餘779區間資料(變數)之人工處理資料,此兩筆皆為高維度資料,皆約有650個觀察值。高維度資料因變數過多,除了分析不易外,亦造成運算時間較長。故本研究目的即探討在有效的維度縮減方式下,找出最小化分錯率的方法。 本研究先比較分類方法-支持向量機、類神經網路和分類迴歸樹之優劣,再將較優的分類方法:支持向量機和類神經網路,應用於維度縮減資料之分類。本研究採用之維度縮減方法,包含離散小波分析、主成份分析和主成份分析網路。根據分析結果,離散小波分析和主成份分析表現較佳,而主成份分析網路差強人意。 本研究除探討以上維度縮減方法對此病例資料庫分類之成效外,亦結合線性維度縮減-主成份分析,非線性維度縮減-主成份分析網路,希望能藉重疊法再改善僅做單一維度縮減方法之病例篩檢分錯率,根據分析結果,重疊法對原始資料改善效果不明顯,但對人工處理資料卻有明顯的改善效果。 / In this paper, we study the serum protein data set of prostate cancer, which acquired by Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOF-MS) technique. The data set, with four populations of prostate cancer patients, includes both raw data and preprocessed data. There are around 48000 variables in raw data and 779 variables in preprocessed data. The sample size of each data is around 650. Because of the high dimensionality, this data set provokes higher level of difficulty and computation time. Therefore, the goal of this study is to search efficient dimension reduction methods. We first compare three classification methods: support vector machine, artificial neural network, and classification and regression tree. And, we use discrete wavelet transform, principal component analysis and principal component analysis networks to reduce the data dimension. Then, we discuss the dimension reduction methods and propose overlap method that combines the linear dimension reduction method-principal component analysis, and the nonlinear dimension reduction method-principal component analysis networks to improve the classification result. We find that the improvement of overlap method is significant in the preprocessed data, but not significant in the raw data.
78

多重群集的偵測研究 / A study of methods for detecting multiple clusters

黃柏誠, Huang, Bo Cheng Unknown Date (has links)
檢測某些地區是否有較高的疾病發生率,亦即群集(Cluster)現象,是近年來空間統計(Spatial Statistics)在流行病學的主要應用之一,常見的偵測方法包括SaTScan (Kulldorff, 1995)及Spatial Scan Statistic (Li et al., 2011)。這些方法多半大都採用一次性偵測,也就是比較疑似群集之內外相對風險(Relative Risk),如此確實可提高計算效率,同時檢視所有疑似群集。然而,一次性偵測會受到群集外其他發生率較高群集的影響,對於相對風險較小群集的偵測能力過於保守(Zhang et al., 2010)。 本文以多重群集偵測為研究目標,以逐次分析的方式修正SaTScan等群集偵測方法,逐一篩選出發生率較高的顯著群集,並探討逐次分析在使用上的時機及限制。除了透過電腦模擬,測試逐次群集分析的改進效果,我們也分析臺灣地區的癌症死亡率,比較偵測結果的差異。研究發現,逐次群集偵測確實能提高相對風險較小群集的偵測能力,像是在相對風險不大於1.6的群集時尤其有效,但若相對風險大於1.6時,SaTScan的偵測能力不受多重群集的影響。 / Cluster detection, one of the major research topics in spatial statistics, has been applied to identify areas with higher incidence rates and is very popular in many fields such as epidemiology. Many famous cluster detection methods are proposed, such as SaTScan (Kulldorff, 1995) and Spatial Scan Statistic (Li et al., 2011). Most of these methods adapt the idea for comparing the relative risk inside and outside the suspected clusters. Although these methods are efficient computationally, clusters with smaller relative risk are not easy to be detected (Zhang et al, 2010). The goal of this study is to apply the idea of sequential search into SaTScan, in order to improve the power of detecting clusters with smaller relative risk, and to explore the limitation of sequential method. The computer simulation and empirical study (Taiwan cancer mortality data) are used to evaluate the sequential SaTScan. We found that the Sequential method can improve the power of cluster detection, especially effective for the cases where the clusters with relative risk not greater than 1.6. However, the sequential method also suffers from identifying false clusters.
79

住宅都市更新案對於周邊風環境與熱環境之影響 / The influence of Urban Renewal Residential Project on Ambient Wind and Thermal Environment

江文勇, Chiang, Wen Yung Unknown Date (has links)
都市更新是為改善都市環境之重要方法之一,因此,本研究係透過都市更新住宅案例在更新前後與相關環境因子進行分析,藉由CFD(Computational fluid dynamics)模擬方式來釐清都市更新完成後周邊風環境與熱環境之影響狀況。研究結果顯示,住宅都市更新案對於周邊風環境與熱環境之影響,就風環境係屬顯著,而熱環境得視個案而定,同時主要影響區域約略在100~150公尺之範圍內。而模擬結果亦顯示,建築物低樓層的退縮、棟距調整、鋪面材質更改將會影響更新後之風環境與熱環境。 建議未來可將模擬範圍、建築物退縮及棟距距離及地面材質納入都市更新風環境與熱環境之評估準則,以規範明確之環境審議機制,並使規劃評估者有可遵循之依據,亦可確保模擬的可靠度。 / Urban renewal is one of the most important ways to improve the urban environment. Therefore,this study conducted an analysis of environmental factors in residential cases before and after urban renewal and clarified the impact of urban renewal on the wind environment and the thermal environment of the ambient areas using computational fluid dynamics (CFD) simulation. The results of the study showed that the residential cases had a consistently significant impact on the wind environment, while the impact on the thermal environment varied from case to case. The main impacted area fell within a radius of 100~150 m. According to the results of the simulation, the shrink of buildings’ low floors, adjustments to building distance, and changes in paving will impacted the wind environment and the thermal environment following urban renewal. In the future, we recommend that researchers include evaluations of the wind environment and thermal environment of urban renewal in the scope of simulation, shrink of buildings, building distance, and paving in order to clearly determine the mechanisms for environmental review for evaluators’ reference and ensure the reliability of the simulation.
80

多維風險分析-實證研究 / Multidimensional risk analysis-demonstration research

蘇愛鈴, Su,Ailing Unknown Date (has links)
Fong與Vasicek(1997)提出風險分析應考慮敏感度分析、風險值及壓力測試,才能完整揭露投資組合的風險狀況。其中風險值的計算,不僅考慮二階風險,並且利用三階動差進行偏態修正。本文除了以變異數-共變異數法、歷史模擬法及蒙地卡羅模擬法此三種方法計算風險值,並利用Fong與Vasicek(1997)偏態修正法及Cornish-Fisher偏峰態修正法來做偏態及峰態的修正。而後再利用概似比檢驗法、回溯測試百分比法及Z檢定法作為驗證風險值模型的評比工具。我們建議在95%及99%的信賴水準下,求算風險值可利用Cornish-Fisher所提出的方法修正偏態及峰態。 / Fong and Vasicek (1997) mentioned that risk analysis should include sensitivity analysis, value at risk (VaR) and stress testing, in order to capture portfolio risk. The calculation of VaR should not only consider the second moment but should also adjust the skewness using the third moment. In this article, we determine VaR by employing three methods, the variance covariance, the historical simulation and the Monte Carlo simulation methods. In addition, we also adjust VaR for the skewness and kurtosis using the methods developed by Fong and Vasicek (1997) and Cornish-Fisher. Then, the likelihood ratio test, back testing and the Z-test are used to verify the VaR model. Our final test results suggest that calculating VaR should be adjusted for the skewness and the kurtosis as shown by the method proposed by Cornish Fisher in the 95% and 99% confidence intervals.

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