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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.
41

報酬分配不確定與國際資產選擇 / International portfolio diversification with knightian uncertainty

林曉伶, Lin, Hsiao-Ling Unknown Date (has links)
自1970年代起, 就有財務經濟學家注意到一現象的存在: 一國的投資者所持有的外國資產占其所擁有的財富的比例, 與理論上所得的比例相較之下, 小了許多. 也就是, 投資者所持有的資產仍集中於國內資產. 這一現象稱為"本國偏向". 本文的主要目的是希望能夠為 "本國偏向" 的現象,提出理論上的可能解釋. 我們藉由在模型中導入Knightian 不確定性下, 投資者對報酬分配不確定厭惡, 探討投資者國際資產選擇行為. 我們得到了在Knightian 不確定性下, 投資者所持有的外國風險性資產的比例確有偏低的傾向.又若國際資本市場的訊息不對稱, 而造成投資者對於本國資本市場的報酬分配不確定程度, 異於對外國資本市場的報酬分配不確定程度時, 投資者會因對外國資本市場的報酬分配不確定程度較高, 而再降低外國風險性資產的持有比例.由所得結果, 可以發現投資者在估計風險性資產的可能報酬的機率分配時, 所產生的不確定性, 很有可能是迼成投資在做國際資產選擇時, 仍將大部份的財富集中於國內的資本市場的原因之一. 這提供了在未來探討 "本國偏向" 現象時, 一個可以參考的方向. / This paper studies the "home bias" puzzle. With homw bias, domestic investors hold a substantially larger proportion of thier wealth portfolios in domestic assets than standard portfolio theory. In the absence of th home bias, investors would optimally diversify away domestic output risk. We suggest that decision-makers do not have full knowledge of the probabilities of the state fo nature. Using a partial equilibrium representiative agent model, we show how the agent allocates his wealth by the presence of Knightian uncertainty. Under some conditions, we derive and simulate the patterns of diversification for agent who maximizes expected utility and simultaneously minimizes uncertainty of probability, attaching less weight to foreign risky assets. Consequently, we argue that the presence of Knightian uncertainty should be added to the explanatory factors that account for the observed diversification patterns.
42

補習班成人學生之內外控人格特質、不確定感、社會支持、考試因應策略與生活適應關係之研究

成靜傑 Unknown Date (has links)
本研究旨在探討補習班成人學生之內外控人格特質、不確定感、社會支持與考試因應策略對生活適應影響的歷程。 研究樣本係自台灣北、中、南區補習班抽樣512位至21至48歲的成人學生。以「簡式內外控量表」、「準備考試不確定量表」、「社會支持量表」、「考試壓力因應行為量為」和「生活適應量表」為研究施測工具。所得資料以次數分配、相關分析、徑路分析等統計方法處理。 研究結果發現,在補習班成人學生的生活適應方面,內控傾向較高、社會支持較多及採取問題導向因應策略者其生活適應狀況較佳,而不確定感較高及採取情緒導向因應策略者,其生活適應較差。在壓力因應策略的使用方面,內控傾向較高和社會支持較多者較傾向採取問題導向因應策略,不確定感較高者較不傾向使用問題導向因應策略。而內控傾向較低、個人內在不確定感較高和工具性社會支持較高者,則較傾向採取情緒導向因應策略。 其次,以徑路分析解釋內外控傾向、社會支持、不確定感和壓力因應策略對生活適應之影響的研究結果指出,工具性社會支持和個人內在不確定感會透過問題導向因應策略而影響學習適應。內外控傾向、工具性社會支持、情緒性社會支持和個人內在不確定感會透過情緒導向因應策略而影響身心適應。此外,影響補習班成人學生學習適應的主要因素是個人內在不確定感和工具性社會支持,而影響身心適應的主要因素則是情緒導向因應策略和個人內在不確定感。亦即個人內在不確定感較低以及工具性社會支持較高的補習班成人學生在學習適應方面的狀況較佳,而較不採取情緒導向因應策略以及個人內在不確定感較低的補習班成人學生在身心適應方面的狀況較佳。顯見不論是在學習適應方面或身心適應方面,個人內在不確定感在影響補習班成人學生的生活適應上扮演著重要的因素,此發現可供往後在壓力或生活適應方面的相關研究加以繼續進一步探討。 針對以上結果,提出綜合討論及後續研究在對象、方法、工具以及變項上的建議,並對補習班學生之壓力因應及生活適應、補習班對學生之服務、教育主管行政機關之管理等方面提出建議。
43

時間數列之核密度估計探討 / Kernel Density Estimation for Time Series

姜一銘, Jiang, I Ming Unknown Date (has links)
對樣本資料之機率密度函數f(x)的無母數估計方法,一直是統計推論領域的研究重點之一,而且在通訊理論與圖形辨別上有非常重要的地位。傳統的文獻對密度函數的估計方法大部分著重於獨立樣本的情形。對於時間數列的相關樣本(例如:經濟指標或加權股票指數資料)比較少提到。本文針對具有弱相關性的穩定時間數列樣本,嘗試提出一個核密度估計的方法並探討其性質。 / For a sample data, the nonparametric estimation of a probability density f(x) is always one point of research problem in statistical inference and plays an important role in communication theory and pattern recognition. Traditionally, the literature dealing with density estimation when the observations are independent is extensive. Time series sample with weak dependence, (for example, an economic indicator or a stock market index data), less in this aspect of discussion. Our main purpose is concerned with the estimation of the probability density function f(x) of a stationary time series sample and discusses some properties of this kernel density.
44

環境不確定下資本預算程序對公司績效影響之研究 / Capital budgeting process and performance under uncertainty

尤俊欽, Yu,Jyun Ching Unknown Date (has links)
本研究的目的有二: 1. 針對台灣前五百大製造業做研究,了解環境不確 定程度對公司使用資本預算方法精密程度的影響,及資本預算程序精細程 度和公司績效的關係。 2. 針對環境不確定程度、資本預算程序精密程度 、公司績效三者,進行假說檢定,以了解在何種環境不確定程度下,應採 用何種資本預算程序,以提高更多的績效,幫助經理人選擇合適的資本預 算方法。主要的研究方法有四: 1. 文獻探討,包括資本預算理論及國內 外的實證研究。 2. 問卷調查,以郵寄方式寄給國內前五百大製造業廠商 的財務部門。 3. 人員深度訪談,於問卷回收後,針對有寄回問卷的廠商 ,以隨機抽樣方式,抽取數家廠商,作深度的訪談,以確定回收問卷資料 的正確性。 4. 統計分析,主要以複迴歸模式來驗證假說。研究結果顯示 如下:(一)國內製造業者傾向於使用較不精細的資本預算程序。國內製 造業者除了在專案的事先規劃方面有較多的努力外,不論在管理科學工具 的使用、敏感性分析與電腦模擬技術及事後的稽核與檢討等重要的資本預 算程序,似乎沒有特別的重視與執行。再者,在專案的評估技術方面,還 是以會計報酬率法、回收期間法較受製造業者的歡迎。(二)上市公司比 非上市公司採用較精細的資本預算程序。而推估其原因可能是上市公司的 規模較大,有足夠的資源及評估專案來支持專責部門的成立與運作,而且 受到投資大者的監督,因而採用較精細的資本預算程序。(三)環境不確 定程度愈高的公司傾向於使用愈精細的資本預算程序。無論以經理人對環 境的主觀知覺或是資產報酬率的標準差來衡量環境的不確定性,公司所面 臨環境的不確定程度與公司所使用資本預算精細程度間存有顯著的正向關 係。(四)環境不確定性較高的公司採用愈精細的資本預算程序將可產生 愈高的公司績效。故對於環境不確定性較高的公司應採用較精細的資本預 算方法,而環境不確定性較低的公司則在成本效益的考慮下,只需作基本 的分析即可達到一定的績效水準。
45

奎因翻譯的不確定說及其相關問題 / Quine's Indeterminacy of Translation and the Relative Questions

林從一, Lin, Chung I Unknown Date (has links)
奎因 (W. V. Quine)的「翻譯的不確定說」(indeterminacy of tran- slation),不僅在他自己的哲學體系中佔有重要的地位,在當代分析哲學 中也是一個非常重要的理論。「翻譯的不確定說」不僅主張,我們翻譯另 一個語言時,會有翻譯上的不確定性;而且主張,對鄰居語言的翻譯,也 會有不確定的情形;甚至,它也主張,在第一人稱中,我使用的語言所指 涉的東西到底是什麼,仍是不可確定的。本文的目的,是想追究兩個問題 :第一,奎因以什麼策略或理論論證出「翻譯的不確定說」?第二,「翻 譯的不確定說」可以合理地適用於什麼範圍?關於第一個問題,本文將從 Word and Object 第二章中,奎因所提的「徹底翻譯」(Radical Translation) 的概念開始討論,因為「翻譯的不確定說」是從這裡關始 建立的,而且,在「徹底翻譯」的討論中,可以幫助我們更深入地研究奎 因是以什麼理論支持「翻譯的不確定說」。本文第二章就分別討論三種奎 因對「翻譯的不確定說」的論證進路:「整體論」、「物理理論的不可限 定說」(underdeterminacy of physical theory)和「字詞指涉的不可測 度說」(Inscrutability of reference of terms ) 。最後,本文認為「 整體論」是其中最強的論證進路。關於第二個問題,本文從奎因的「存有 相對性」 (Ontological rela- tivity) 的觀點開始討論。「存有相對性 」主張,除非相對於背景語言,否則不能說對象語言中字詞指涉的東西是 什麼;而這個存有相對性擴展的程度,就是「翻譯的不確定說」適用的程 度。本文認為,它只能適用於對另一個語言、或對另一個言說者的翻譯上 ,並不像奎因所主張的可以適用於第一人稱 (first person) 中、對自己 語言的再詮釋上。本文反對奎因的理由不是基於直覺,而是基於奎因理論 本身的不一致之處,以及基於幾項對第一人稱中翻譯不確定性優缺點的反 省,來反對奎因的這項主張。第一個問題可以幫助我們瞭解第二個問題, 不過它不僅是用來協助我們釐清問題,它本身就是一個需要詳細討論的主 題;第二個問題,也是戴維森 ( Donald Davidson) ,色勒 (John Searle) ,克爾克(Robert Kirk) 以及方萬全先生所關心的問題,它會涉 及私有語言、語意的公共特質和同一語言的判定等若干哲學問題。對這個 問題,本文的立場和方萬全先生最接近,雖然所持的理由不盡相同。在第 一、二章中,討論的是第一個問題,三、四章中討論的是第二個問題。
46

針對複合式競賽挑選最佳球員組合的方法 / Selecting the best group of players for a composite competition

鄧雅文, Teng, Ya Wen Unknown Date (has links)
在資料庫的處理中,top-k查詢幫助使用者從龐大的資料中萃取出具有價值的物件,它將資料庫中的物件依照給分公式給分後,選擇出分數最高的前k個回傳給使用者。然而在多數的情況下,一個物件也許不只有一個分數,要如何在多個分數中仍然選擇出整體最高分的前k個物件,便成為一個新的問題。在本研究中,我們將這樣的物件用不確定資料來表示,而每個物件的不確定性則是其帶有機率的分數以表示此分數出現的可能性,並提出一個新的問題:Best-kGROUP查詢。在此我們將情況模擬為一個複合式競賽,其中有多個子項目,每個項目的參賽人數各異,且最多需要k個人參賽;我們希望能針對此複合式競賽挑選出最佳的k個球員組合。當我們定義一個較佳的組合為其在較多項目居首位的機率比另一組合高,而最佳的組合則是沒有比它更佳的組合。為了加快挑選的速度,我們利用動態規劃的方式與篩選的演算法,將不可能的組合先剔除;所剩的組合則是具有天際線特質的組合,在這些天際線組合中,我們可以輕易的找出最佳的組合。此外,在實驗中,對於在所有球員中挑選最佳的組合,Best-kGROUP查詢也有非常優異的表現。 / In a large database, top-k query is an important mechanism to retrieve the most valuable information for the users. It ranks data objects with a ranking function and reports the k objects with the highest scores. However, when an object has multiple scores, how to rank objects without information loss becomes challenging. In this paper, we model the object with multiple scores as an uncertain data object and the uncertainty of the object as a distribution of the scores, and consider a novel problem named Best-kGROUP query. Imagine the following scenario. Assume there is a composite competition consisting of several games each of which requires a distinct number of players. Suppose the largest number is k, and we want to select the best group of k players from all the players for the competition. A group x is considered better than another group y if x has higher aggregated probability to be the top ones in more games than y. In order to speed up the selection process, the groups worse than another group definitely should first be discarded. We identify these groups using a dynamic programming based approach and a filtering algorithm. The remaining groups with the property that none of them have higher aggregated probability to be the top ones for all games against the other groups are called skyline groups. From these skyline groups, we can easily compare them to select the best group for the composite competition. The experiments show that our approach outperforms the other approaches in selecting the best group to defeat the other groups in the composite competitions.
47

混沌及不確定環境下的成長策略-以S公司為例 / The growth strategy in chaos and uncertain environment

彭國書 Unknown Date (has links)
在全球經濟化形式下,新資訊時代的變化帶來企業所面臨環境有更高的不確定性,市場變幻莫測,國際經濟環境動盪,企業的生存面臨著前所未有的挑戰,世界金融危機所帶來的困境、裁員、企業升級等危機,這些都迫使企業經營者不得不去思考如何應對環境快速變化之特性及採取必要的經營策略。企業在劇烈的環境變化中如何發揮自身的競爭優勢,並與其他企業合作互贏,來應對外部持續變化的不確定環境。 本研究由文獻資料分析出企業所面臨不確定環境中所應用的策略,確認不確定環境中可採用的策略方法,對競合策略、企業文化、企業創新與轉型、SWOT分析法及平衡計分卡進行歸納總結。 本文以膠帶行業一集團中的子公司為研究對象,對膠帶行業的產業結構進行分析,重點介紹大陸PVC市場並對膠帶行業未來的發展趨勢進行預測展望。再對企業目前所處的策略地域、經濟環境、企業環境、環保趨勢進行分析。運用價值網、SWOT分析法、平衡計分卡等分析方法對企業目前的運營狀況進行總結,研究企業現推行的經營策略及未來發展之路,並在最後得出企業實施策略後的成長效益進行總結。 / In the global economic times, the change of new information age cause the business has to faced greater uncertainties environment, the market is uncertain, international economic environment unrest, the enterprise is faced with unprecedented challenges and the world financial crisis brought difficulties, downsizing and enterprises upgraded etc. All these forces managers to think how to solve the problem of environmental rapid changes and take necessary measures . Enterprises how to play its own competitive advantage and cooperation with other enterprises in the severe changes environmental , how to fit the constantly changing environment. This research based on the documentation to analysis of strategy when enterprise in the unsure environment.This research to confirm the strategy could adopted in the unsure environment. Summarize the Co-opetition,corporate culture, innovation and change, swot analysis and balanced scorecard This thesis study with a group of the subsidiary in the tape industry.To analysis the industrial structure and focus on the plastic PVC market of China.The future development tendency of tape industry forecasted.Then analysis strategic areas of enterprises, business environment, corporate environment and the trend of environmental protection.Analysis the present state of the enterprise with the vuale net,SWOT anaylsis and balanced scorecard to research the present operate strategy and the direction of future development.At last,come to the benefits of growth after the enterprises implement strategy.
48

產能限制與個人需求不確定性對耐久財獨佔廠商訂價策略之影響 / Durable Goods Monopoly with Capacity Constraint and Individual Demand Uncertainty

張偉瑱, Chang, Wei Chen Unknown Date (has links)
本文將探討當一販售耐久財的獨佔廠商面臨到商品產量限制以及市場上存在著個人需求不確定性時的最適訂價模式。此外本文也透過分析不同時期消費者所面臨的每期使用價格變化來說明當消費者存在個人需求不確定性時,廠商於兩期使用價格的設定會出現異於Coasian耐久財模型的兩期使用價格設定。當商品效用在第二期出現壞結果時低於一定標準時,廠商兩期使用價格訂價模式將出現第一期使用價格下降而第二期使用價格反而上升的現象,甚至可能出現第二期使用價格高於第一期使用價格的現象。而這與Coasian耐久財模型所呈現的兩期使用價格訂價模式是大不相同。 我們發現當廠商採取非價格承諾的訂價策略且廠商產能處於一定的數值時,廠商採取讓消費者面臨限量風險的訂價策略可獲得較Coasian耐久財模型更高的利潤。由此可見產能限制將可使廠商在採取非價格承諾的訂價策略下仍能透過讓消費者面臨限量的風險來保有獨佔力並且賺取較高利潤。 / This paper will investigate the best pricing strategy for durable goods monopolist with capacity constraint and individual demand uncertainty. We also introduce the concept of “per-period usage price” and illustrate the difference between traditional Coasian durable goods pricing strategy and ours. When the product utility turns out to be a bad outcome and its value is lower than the certain standard, first period’s per-period usage price will decrease while second period’s per-period usage price will increase simultaneously. This consequence is totally different from Coasian durable goods model. When monopolist use non-commitment pricing strategy and face capacity constraint, monopolist will set the price for exerting the risk of rationing to consumers which will help monopolist gain higher profit than Coasian durable goods model. This shows that capacity constraint will help monopolist keep monopoly power and gain higher profit.
49

匯率不確定性與台灣對中國大陸出口關係 / The Relationship of Exchange Rate Volatility and Taiwan Export to Mainland China

曾慧容, Tseng, Hui Jung Unknown Date (has links)
本文探討匯率不確定性與台灣對中國大陸出口之關係,模型中參考Cushman (1986) 觀點加入第三國變數之效果。研究期間以1997年至2010年之季資料,同時考慮總合資料以及部門別資料,並以GARCH估計實質匯率波動性。第三國則利用出口近似度的計算選擇了前四大競爭國,分別為南韓,日本,馬來西亞及新加坡。此外,部門則以HS二碼分類選擇出口至中國大陸前四大之部門,包括機械與電子、精密儀器、橡膠與塑膠類產品及化學品。 本文檢定變數是否有單根。若有單根則進一步檢定這些變數是否存在共整合關係。在確定存在共整合關係後,利用完全修正最小平方法及誤差修正模型進行估計。本文實證結果顯示:匯率不確定性對出口量有負向之影響關係。就部門而言,本文探討的四個部門之結果也反映匯率不確定性對出口具有負向影響,但是以電子產品及塑膠橡膠類之影響最為顯著。 / This paper investigates the relationship between exchange rate volatility and Taiwan’s exports to Mainland China. In the empirical model, the third country effects suggested by Cushman (1986) are considered. GARCH model is employed to estimate real exchange rate volatility. Both aggregate and sectoral quarterly data covering 1997 to 2010 are used in our sample. The third countries are determined by export similarity. The top 4 countries with the highest degree of export similarity are chosen, including South Korea, Japan, Malaysia and Singapore. In addition, the top 4 Taiwan’s exporting sectors are examined respectively, including machinery and electronic equipment, precision equipment, rubber and plastics, chemicals industries. We first test for unit root of the variables used in the study, and then check the existence of co-integration between the variables with unit root. After confirming the existence of co-integration relationship, we use FMOLS (Fully Modified OLS) and VECM (Vector Error Correction Model) to estimate the coefficients. Our empirical results suggest that there is a significantly negative effect of exchange rate volatility on Taiwan’s total exports. They also indicate that there is a negative relationship between exchange rate volatility and Taiwan’s sectoral exports. Among the top 4 exporting sectors, exchange rate volatility tends to have higher impacts on the machinery and electronic industry as well as chemical industry.
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同理心對於決策中觀察學習的調節作用 / Empathy modulates observational learning in decision making

高常豪 Unknown Date (has links)
生活中許多決策情境是「不確定下的決策(decisions under uncertainty)」,只瞭解選項的結果,不知道結果發生的機率。人們會累積經驗,以學習到適當的決策。許多證據支持,自身會透過增強學習(reinforcement learning)機制學習,根據每次獲得的經驗,調整對於選項的期望,之後選擇期望最大的選項,幫助做出適當的決策。經驗可以透過自身決策或觀察他人決策所獲得,然而,過去較少研究探討觀察學習。因此,本研究欲探討決策中的觀察學習,並釐清同理心對於觀察學習的調節作用。實驗一中,改善過去了研究限制,量測膚電反應、學習速率與行為表現,讓參與者在自身學習、觀察他人與觀察電腦情境進行作業,並透過同理心問卷測量參與者的同理心特質。結果顯示,觀察學習在正向學習與負向學習不同,正向學習為趨向優勢選項,負向學習為避開劣勢選項。正向學習在三種學習情境中無任何差異,負向學習在觀察他人學習時,會受到同理心的調節作用。同理心分數越高,觀察他人的負向行為表現越好,觀察他人負向回饋的膚電反應越大。實驗一只透過問卷測量同理心,無法推論因果關係,因此實驗二直接操弄了不同的同理程度。回饋呈現的同時,呈現他人的情緒或中性臉孔圖片,以引發參與者的同理程度高或低。實驗中,量測回饋相關負波(Feedback-Related Negativity,FRN)、學習速率與行為表現。如同實驗一,只有負向學習受到同理程度不同的影響。同理程度高時,負向學習表現較好。FRN則顯示了同理程度與預期性的交互作用,同理程度低時,與過去研究一致,非預期FRN比預期FRN更加負向;同理程度高時,則無此預期性效果。雖然FRN無預期性差異,但依然能學習到符號機率,行為表現不受影響,推測可能有其他系統參與決策學習。綜上所述,本研究顯示,只有負向學習中,觀察學習會受到同理心的調節,同理心越高,行為表現越好。 / In daily life, we made many decisions under uncertainty. In each decision, we know only the outcome but no probabilities of the outcome. We have to accumulate the experience to learn adaptive decisions. Bunches of studies have shown that people may learn adaptive decisions by reinforcement learning. People modified the expectation for each option according to decision feedbacks, and, in the next time, chose the option with the maximum expectation. People can receive feedback from decisions making by self or others. However, fewer studies examined observational learning in decision making. Therefore, present research would clarify observational learning in decision making, and examine how empathy modulated observational learning. In experiment 1, skin conductance response, learning rate and behavioral performance were recorded and analyzed. Participants would learning decisions in different situations of self learning, observing others and observing computer. The questionnaire of empathy was also measured to examine its modulation in observational learning. The results showed that there were difference in positive learning and negative learning. Positive learning is to approach to the advantageous option, while negative learning is to avoid from the disadvantageous option. In positive learning, there were no difference among the three learning situations, but, in negative learning, empathy would modulate learning by observing others. The higher the empathy score was, the better the behavioral performance of negative learning was. Moreover, the skin conductance response when participants observing others’ negative feedback positively correlated with the empathy score. In experiment 2, the empathy level was manipulated by display pictures of others faces with feedback. Displaying the emotional faces or neutral faces would induce high or low empathy level for others, respectively. The feedback-related negativity (FRN), learning rate and behavioral performance were recorded and analyzed. Similar to experiment 1, only the negative learning was modulated by the empathy level. When participants were induced high empathy level, the behavioral performance was better. The results of FRN showed the interaction between empathy levels and expectancy of feedback. When participant’s empathy level was low, unexpected FRN was more negative than expected FRN. This result was consistent with previous studies. Nevertheless, when participant’s empathy level was high, there was no difference between unexpected FRN and expected FRN. Although FRN didn't show the effect of expectancy, participants could still learn the probabilities of each signs and made adaptive decisions. This result may result from other systems involved in observational learning. From the results of experiment 1 and 2, present research showed that, only in negative learning, observational learning was modulated by empathy, and the higher the empathy level was, the better the behavioral performance was.

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