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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.
281

上市公司購併宣告對股價影響之研究-以電子業及食品業為例

沈建良, Chern, Jiann-Liang Unknown Date (has links)
本研究之研究目的旨在探討國內電子業及食品業上市主併公司進行購併活動對股價所產生的影響。研究期間為民國76年1月1日至88年12月31日,經搜集相關資料後共取得83個符合條件的購併樣本,電子業及食品業分別為53個及30個。本研究以購併宣告日前21日至宣告日前120日為市場模式之估計期,而以購併宣告日前20日至宣告日後20日為事件觀察期,採用事件研究法分析主併公司的購併宣告效果。除此之外,本研究亦以三日累積平均異常報酬為應變數,而以購併地點、購併型態、公司規模、負債比率、稅前淨利率及內部人士持股比例為自變數進行橫斷面複迴歸分析,試圖找出影響累積平均異常報酬的因素,經由實證分析後得到以下研究結論: 1.電子業與食品業上市公司購併宣告對股價有正面的影響,但電子業之購併宣告效果大於食品業。 2.電子業上市公司相關購併宣告對股價的影響程度大於非相關購併宣告,而食品業上市公司相關購併宣告對股價的影響程度小於非相關購併宣告,但效果並不顯著。 3.電子業上市公司國際購併宣告對股價的影響程度小於國內購併宣告,而食品業上市公司國際購併宣告對股價的影響程度大於國內購併宣告。 4.不論是電子業或是食品業,負債比率與三日累積平均異常報酬均有顯著的關係,但這兩個產業的結果卻完全相反。 最後,本研究以研究結論,分別針對上市公司、投資者、政府主管機關及後續研究者提出一些建議,期盼這些建議能夠對於其從事相關決策、學術研究時有所助益。
282

台灣地區上市公司股票評價模式之研究-以電器電纜業為例

洪美慧, Hong, Mei-Huei Unknown Date (has links)
有鑑於國內投資人已漸漸注重基本分析,因此本研究將以電器電纜業為例,針對一般股票評價模式作研究。首先比較各種評價理論所計算出的結果與市場實際價格之間的落差,進行研究之後,分析各種評價法落差的情形,進而尋求對電器電纜業最適當的評價方法。並以此預測電器電纜公司88年底之實質價值,再與實際價格比較之後,提供投資大眾買進賣出之參考。 首先將過去文獻資料中影響公司成長的因素,利用相關分析以及逐步迴歸法,找出影響電器電纜公司銷售額成長的主要因素,以這些因素建構一條迴歸方程式,作為計算各公司未來成長率的依據。以過去最常用到的六種評價模式:現金流量折現法、會計盈餘折現法、本益比法、價格/帳面價值比法、價格/銷售比法及選擇權定價法來研究其效果。實際作法是分別計算各電器電纜公司79年至83年的價值,再與其各年度之實際股價比較,以Theil’s U值找出最佳之評價模式。最後則是利用所選出最適合我國電器電纜業的股票評價模式,配合第一部份所得之成長率,推算電器電纜業公司89-93年之財務報表,藉以算出其88年底的實質價值。 本研究之實證結果為:由總體經濟自變數之相關分析中可得,本研究在經濟面採用我國經濟成長率(E1)、台幣兌美元匯率(E2)、躉受物價指數(E4)、貨幣市場利率(E5)以及股票價格指數(E6)等五個變數;再加上影響公司營運成果的11個財務比率,引入逐步迴歸模式中。結果發現電器電纜業銷售額模式中,投入變數順序為固定資產週轉率(C4)、存貨週轉率(C3)、總資產週轉率(C5)、賺得利息倍數(C7)、躉售物價指數(E4)、負債比率(C6)以及貨幣市場利率(E5)。第二部分的實證結果結果發現市價帳面價值法為電線電纜業最佳的評價模式,其次為市價銷售額法。因此本研究最後以市價帳面價值法來計算電器電纜公司88年底之股價,提供大眾作為投資時的參考。
283

運用現金流量資訊預測企業財務危機之實證研究 / Using Information of Cash Flows to Predict Financial Distress

李智雯, Lee, Jr-Wen Unknown Date (has links)
企業發生財務危機,不僅使其經營陷入生死關頭之掙扎,更影響眾多投資人、債權人的利益,對於整個經濟環境亦造成一定的衝擊。因此,如何提早察覺企業之危機,以減少社會成本,實值得我們深入研究。 本研究主要目的為評估現金流量表揭露之資訊,於預測企業財務危機的有用性。本研究欲探討現金流量資訊是否為預測企業財務危機的良好指標,於建構企業財務危機預警模式之際,加入現金流量的財務指標是否會比僅以傳統財務比率建立之預警模式,更具預測能力。 本研究採用配對樣本設計,在我國上市公司中共選取了35家危機公司與68家正常公司。並利用Logit迴歸分析分別建立現金流量模式、應計財務模式與綜合模式,得到以下結論: 一、在財務危機發生之前一至三年,本研究所使用的應計基礎財務比率並非皆適合用來區分危機公司與正常公司。 二、除了營業活動現金流量相關比率具有顯著的區別能力外,部分投資與融資活動現金流量相關比率亦提供額外的財務危機警訊。 三、現金流量比率預警模式之預測力表現不遜於應計基礎比率模式;但在應計基礎比率中加入現金流量比率,並未顯著提高模式的預測能力。 / The objective of this study is to assess the usefulness of cash flow disclosures in the prediction of financial distress. This study also determines whether cash flow ratios are good indicator of financial distress and whether adding cash flow ratios in prediction model can improve the predictive ability of the model employing conventional accrual-based ratios. Using a matched pair design, this study examines a sample of 35 distress firms along with 68 non-distress firms. Also, a logistic regression analysis is used to establish the financial distress model with and without cash flow variables respectively, in order to test the hypotheses developed by this study and to derive the conclusion. The findings of this study are as follows. 1. During the period between 3 years to 1 year before financial distress, the accrual-based ratios used in this study aren't all good predictor in financial distress model. 2. The discriminate ability of operating cash flow data is significant. Also, the investing and financing cash flow data provide additional information in the prediction of business distress. 3. Cash flow ratios provide a superior measure for the prediction of financial distress over accrual-based ratios. However, no significant evidence shows that using cash flow ratios in conjunction with accrual-based ratios can improve the overall predictive power of accrual-based ratios alone.
284

雙變量脆弱性韋伯迴歸模式之研究

余立德, Yu, Li-Ta Unknown Date (has links)
摘要 本文主要考慮群集樣本(clustered samples)的存活分析,而每一群集中又分為兩種組別(groups)。假定同群集同組別內的個體共享相同但不可觀測的隨機脆弱性(frailty),因此面臨的是雙變量脆弱性變數的多變量存活資料。首先,驗證雙變量脆弱性對雙變量對數存活時間及雙變量存活時間之相關係數所造成的影響。接著,假定雙變量脆弱性服從雙變量對數常態分配,條件存活時間模式為韋伯迴歸模式,我們利用EM法則,推導出雙變量脆弱性之多變量存活模式中母數的估計方法。 關鍵詞:雙變量脆弱性,Weibull迴歸模式,對數常態分配,EM法則 / Abstract Consider survival analysis for clustered samples, where each cluster contains two groups. Assume that individuals within the same cluster and the same group share a common but unobservable random frailty. Hence, the focus of this work is on bivariate frailty model in analysis of multivariate survival data. First, we derive expressions for the correlation between the two survival times to show how the bivariate frailty affects these correlation coefficients. Then, the bivariate log-normal distribution is used to model the bivariate frailty. We modified EM algorithm to estimate the parameters for the Weibull regression model with bivariate log-normal frailty. Key words:bivariate frailty, Weibull regression model, log-normal distribution, EM algorithm.
285

應用羅吉特迴規模式分析壽險購買行為 / Using Logisitic regression to analysis life insurance purshasing behavior

陳棻煐, Chen, Feng-Ying Unknown Date (has links)
多樣化壽險商品時代來來臨、壽險業目標市場鎖定的需求,致使「選擇適當的目標市場」和「設計適合目標市場的行銷組合策略」成為保險業者在擬定行銷策略所應注重兩大方向。惟如何選擇最具有吸引力,而又適合本身資源條件及競爭環境的目標市場,則就是行銷理論研究及實務上最重要的一項問題。 綜觀目前國內各研究所的論文中,關於消費者對於保險商品之購買行為的研究,多集中在消費者購買保險的原因或動機之分析上。惟其多是描述性、相關性分析為主,而此類研究方式雖然有其實用性,但其在缺乏「因果關係」的分析下,實無法了解消費者本身之不同,所引起購買意願之不同。再者,其並未進一步針對不同商品,研究影響消費者之所以購買不同商品之因素,係因任何忽略「商品多樣性」的研究,顯然過於簡化影響是否消費者購買保險商品之因素。本文對於消費者購買行為之基本認識為:消費者決定『是否購買』。保險,以及決定『選擇何種』保險的過程是同一的、不可分的。」因此,本文將以「多樣化的保險商品」為前提,來研究消費者決定「是否」購買保險、以及「選擇」購買何種保險之原因或動機。 究竟「消費者本身的差異性」與「是否購買及購買何種保險」之間存在什麼樣的關係,同時也是保險公司在保單設計、搭配、以及保險行銷上不可忽略之重要裁題。本文從于證資料上分析此一問題,以EKB消費者行為模式為理論基礎,依消費者本身的不同的背景、不同投保的動機、不同對保險的認知等等不同追求產品的相對利益為基礎因素,來探討消費者對不同的保險商品的需求。 本文乃以『問卷調查』為研究工具,針對台灣地區 20 歲- 70 歲之消費者為研究對象,實際訪查消費者所偏好之保險商品。共計取得有效問卷 965 份,輔以以效用函數為理論基礎之『羅吉特迴歸模式』計量方式,找出「消費者本身的差異性」與「是否購買及購買何種保險產品」之間的因素,並而建立消費者效用函數,進而預估消費者購買保險機率,促使業者更能設計符合消費者需求之保單組合。 研究結果顯示,在「是否會購買保險」的議題上,發現消費者教育程度不同會影響其購買意願;「保險演講會的舉行」、「親友在保險公司做事」或「自身或家屬曾發生事故」時,亦會明顯提高消費者之購買意願;業務員的上門推銷將是促使消費者引起購買保險的主要動機之一;再者,消資者在購買保險時,最重要之評估準則,則在於壽險期間是否太長、領回的錢值不值得及保費是否會太高等問題。 就「偏好購買不同商品」的議題上,本研究亦就目前市面上較為普遍之十種商品作研究,研究發現影響消費者偏好購買各個商品之因素各有不同,本文亦對其作綜合整理。最後亦針對研究結果,就各個不同保險商品,依其具有顯著水準之人口統計變項作--市場區隔,以期能提供保險公司或業務員在銷售時,可依商品的不同對消費大眾做市場區隔,使業務員或保險公司較易針對消費者不同的需求,做出較適合消費者且較易使消費者接受的保單設計。相信如此一來,非但有助於保險公司之保單設計與行銷,對於保險消費者如何選擇最適合自己的保單,也有相當的助益。 / The main goal of this research is to study the motives of the consumers purchasing the insurance policies and the selecting procedures. The previous researches on this area have been focused on the purchasing motives of each individual consumer. This kind of approach is widely used in practice. However, the consumers are not facing one insurance product but a variety of different insurance portfolios. In this study, we focus on analyzing the consumer-purchasing behavior of insurance portfolios. The logistic regression model is used to estimate the preference of the consumers among different insurance policies. The procedures of this study are summarized in the following: ( 1 )Review the developments of the previous researches and the findings. ( 2 )Design an appropriate questionnaire to collect the valid information and formulate the logistic regression model in this study. ( 3 )Collect the samples from the questionnaire and code this survey into a database system. ( 4 )Estimate the coefficients in the regression model in Step (2) and analyze the results. Finally comment on the findings. Using the logistic regression model is helpful for the marketing department in insurance company to target the appropriate populations and differentiate the various insurance portfolios. In this study, the information from the questionnaire is investigated based on our choice model. Monitoring these effects is beneficial for the managers having concise information in our target markets. Finally, a quantitative model is proposed for Taiwan insurance markets and the recommended marketing strategy.
286

類神經網路之應用-黃金期貨預測 / The application of neural network - forecasting gold future

鐘正良, Chung, Chen Liang Unknown Date (has links)
本研究欲提出一COMEX黃金期貨價格的類神經網路模型,期此一模型能預測出當期的黃金期貨價格。在類神經網路模型方面,採用倒傳遞類神經網路;而其輸入層共有九個處理單元,即影響黃金期貨價格的九個變數,輸出層為一個處理單元,即黃金期貨價格,至於隱藏層則採二層,因黃金期貨價格有波動大、難預測且為非線性的特性。   為證明類神經網路是否有較傳統統計學方法在此一方面有較強的預測能力,所以以此模型與單變量時間數列模型及迴歸分析模型做比較,並以MSE及MAPE作為評估的準則。   在實作方面,研究資料以西元1987年1月至西元1991年12月60筆月資料為訓練樣本;而西元1992年1月至1995年12月48筆月資料為測試樣本。研究結果顯示不論是MSE或MAPE類神經網路模型皆優於迴歸分析模型及時間數列模型。
287

遺傳演算法在非線性時間數列結構改變之分析與應用 / Using Genetic Algorithms to Search for the Structure Change of Non-linear Time Series

阮正治, Juan, Cheng Chi Unknown Date (has links)
近幾年來,非線性時間數列分析一直是時間數列及計量經濟學者所熱衷的研究主題之一,而非線性時間數列結構改變的研究也越來越受到重視。其中的門檻自迴歸模式,雖具有線性模式所不能配適的特性,但模式建構的問題,一直是其在發展應用上的瓶頸。本研究擬以門檻自迴歸模式建構的流程並結合遺傳演算法的最佳化搜尋技術,架構出時間數列遺傳演算法,藉此演算法則及程序,全域性地搜尋最佳的門檻自迴歸模式。 / Non-linear time series analysis is a research topic which the schalors of time series and econometrics are intent on, and the research of structure change of non-linear time series is attentive. Threshold autoregressive model (TAR model) of non-linear time series has some characters which linear model fail to fit while the problem of how to find an appropriate threshold value is still attracted many researchers attention. In this paper, we present about searching the parameters for a TAR model by genetic algorithms.
288

線性羅吉斯迴歸模型的最佳D型逐次設計 / The D-optimal sequential design for linear logistic regression model

藍旭傑, Lan, Shiuh Jay Unknown Date (has links)
假設二元反應曲線為簡單線性羅吉斯迴歸模型(Simple Linear Logistic Regression Model),在樣本數為偶數的前題下,所謂的最佳D型設計(D-Optimal Design)是直接將半數的樣本點配置在第17.6個百分位數,而另一半則配置在第82.4個百分位數。很遺憾的是,這兩個位置在參數未知的情況下是無法決定的,因此逐次實驗設計法(Sequential Experimental Designs)在應用上就有其必要性。在大樣本的情況下,本文所探討的逐次實驗設計法在理論上具有良好的漸近最佳D型性質(Asymptotic D-Optimality)。尤其重要的是,這些特性並不會因為起始階段的配置不盡理想而消失,影響的只是收斂的快慢而已。但是在實際應用上,這些大樣本的理想性質卻不是我們關注的焦點。實驗步驟收斂速度的快慢,在小樣本的考慮下有決定性的重要性。基於這樣的考量,本文將提出三種起始階段設計的方法並透過模擬比較它們之間的優劣性。 / The D-optimal design is well known to be a two-point design for the simple linear logistic regression function model. Specif-ically , one half of the design points are allocated at the 17.6- th percentile, and the other half at the 82.4-th percentile. Since the locations of the two design points depend on the unknown parameters, the actual 2-locations can not be obtained. In order to dilemma, a sequential design is somehow necessary in practice. Sequential designs disscused in this context have some good properties that would not disappear even the initial stgae is not good enough under large sample size. The speed of converges of the sequential designs is influenced by the initial stage imposed under small sample size. Based on this, three initial stages will be provided in this study and will be compared through simulation conducted by C++ language.
289

住宅價格與總體經濟變數關係之研究-以向量自我迴歸模式(VAR)進行實證 / A Study on the Relationship between Housing Price and Macro - economic Variable

黃佩玲, Hwang, Pay Ling Unknown Date (has links)
由於住宅價格變動毫無預警制度,人民往往憑著個人主觀的判斷而決定何時購屋或售屋,而此種主觀判斷住宅市場利多及利空的觀念,對住宅市場的供需會產生失衡現象,因此是否可從經濟面的訊息找到住宅價格變動的答案,使住宅價格在尚未變動前,政府即已掌握資訊,提前做好穩定住宅價格的因應對策,使民眾依其需要而購屋,則是本研究之主要目的。   本研究從文獻中整理出影響住宅價格變動的七個總體經濟變數,這些總體經濟變數包含工資、物價、所得、貨幣供給額、股價、匯率及利率等,並利用向量自我迴歸模式(VAR)進行實證,以便較客觀的獲得變數間的落後期數及暸解變數間雙向、單向及領先、同步、落後情形,且進一步探討住宅價格與每一個總體經濟變數間影響程度大小及影響情形,以釐清各變數之間的關係。   本研究利用VAR模型進行住宅價格與總體經濟變數關係的研究,經由實證,得到下列的結論:   一、實證結果方面   本研究之實證主要有因果關係檢定與分析、變異數分解之分析及衝擊反應之分析三方面,其實證結果如下所述。   (一)因果關係檢定與分析   由因果關係檢定與分析中,得到股價、物價、匯率、貨幣供給額及利率均能做為住宅價格變動的領先指標。   (二)變異數分解之分析   由住宅價格之變異數分解中,得知住宅價格自身的解釋程度僅占三分之一,另三分之二被其他的總體經濟變數所解釋,顯示住宅價格受總體經濟變數的影響相當大;而從其他總體經濟變數之變異數分解中,得知住宅價格變動會干擾到總體經濟變數,而使總體經濟變數受干擾而變動變動。   (三)衝擊反應之分析   從總體經濟變數對住宅價格的衝擊反應分析圖中可以明顯看出除工資外,其餘總體經濟變數變動對住宅價格造成的衝擊均相當明顯,但匯率及利率對住宅價格的衝擊是負向的。   住宅價格對所得、股價、匯率及利率的衝擊相當明顯,而其對匯率的衝擊是負向。   二、政策應用方面 政府的決策過程中常會有時間落後的現象,而本研究實證的目的則是要使政府能事先掌握住宅價格的變動,並提前做好穩定住宅價格的因應對策,減少政府決策過程的時間落後現象,而實證結果應用至政策方面的內容則由以下說明之。   (一)藉由因果關係檢定與分析的實證內容,可以縮短政府對住宅價格不合理變動問題認定落後的時間。   (二)從變異數分解之分析的實證內容中,可以使決策者在解決住宅價格問題時,將行動落後的時間減少。   (三)由衝擊反應之分析中,可以使政府在執行穩定住宅價格政策時,將衝擊落後的時間縮小。 / Since there is no alarm system in the change of housing prices, people often decide when to buy or when to sell based on personal and subjective judgement. Such concept to judge subjectively whether the housing market is bull or bear will cause unequilibrium in the supply and demend of the housing market. There it is possible to find out the answers to the change of housing prices from economic side so that the government can have enough information and can be prepared in the reaction to stabilizing the housing prices, and so that the public can buy house according to their needs is the main purpose of this project.   Seven variables in macroeconomics influencing the change of housing prices have been taken from reative literature, including wage, commodity price, income, money supply, stock price, exchange rate, and interest rate. VAR has been employed to verify so that the more objective lagging period among variable can be known, and the bi-directional, uni-directional, leading, contemporaneous, and lagging situation among variables can be understood. Furthermore, the degree and the status of influence of each macroeconomic variable to the housing price will be investigated to clarify the relations among the variables.   The present project investigate the relations between housing price and macroeconomic variables. We have the following findings:   I、In Empirical Study:   The empirical study in this project includes causal relation test and analysis, the analysis of variable decompositon, and the analysis of impact response. The results are shown in the following:   (I) Causality Test and Analysis   In the causality test and analysis, we find out that stock price, commodity price, exchange rate, money supply and interest rate all can be the leading indicators in the change of housing prices.   (II) The Analysis of Variable Decomposition   It is learned from the variable decomposition of housing prices that housing price can only explain one third of the cause in its change, the other two thirds are explained by other macroeconomic variables. It shows that housing prices are subject to the influence of macroeconomic variables greatly.   From the variable decomposition of other macroeconomic variables, we know that the change in housing prices will affect macroeconomic variables so that the macroeconomic variables will change.   (III) The Analysis of Impact Response   It can be obviously seen from the analysis figure of the impact response of the macroeconomics to housing prices, all macroeconomic variables will cause obvious impact to housing prices expect for wage. However, both exchange rate and interest rate have negative impact to housing prices.   Housing prices' impact to income, stock prices, exchange rate and interest rate is quite obvious, among which, the impact to exchange rate is negative.   II、Policy Application   It is a common phenomenon that there often will be lagging in time in government's decision making. The purise of the empirical study in this project is to let the government to know in advance the change of housing prices and to let the government to know in advance the change of housing prices and to let the government be prepared in the reaction of stabilizing the housing prices to minimize the lagging in the decision making process. The contents of application of the empirical study to policy are explained in the following:   (I) With the empirical results of the change of the causality test and analysis, the time for the government to recognize the unreasonable changes in housing prices can be shortened.   (II) With the empirical results of the analysis of variable decomposition, the decision makers' lagging in the action responding to housing pricescan be minimized.   (III) With the analysis in impact response, the lagging in impact will be minimized when the government executing her housing price stabilizing policy.
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時間數列的模糊分析和預測 / Fuzzy Analysis and Forecasting in Time Series

許嘉元, Sheu, Chia-Yuan Unknown Date (has links)
動態資料往往隨著時間區間取法或測量工具的不同而有差異,此種不確定的特質我們稱為模糊性。但是傳統的時間數列仍是以確定的觀察值來記錄具有模糊性的動態資料。為了更完整的表示一個動態過程,我們考慮模糊時間數列(fuzzy time series)以具有不確定性的模糊集合來取代明確的數值,保持原來的模糊性。 本文探討模糊時間數列中模糊自我迴歸模式(fuzzy autoregressive model簡寫為 FAR 模式)的建構過程,並分別利用此模式來預測中央政府總預算和匯率。FAR 模式乃根據Box-Jenkins(1970)所提出的 ARMA 三階段模式建立的流程並推廣Zadeh(1965)所提出的模糊集合理論而來。在這過程中 ,我們考慮人類思維方法,使FAR 模式更具有彈性且適合未來預測時的需要。而對於所討論的動態過程,也不需要任何模式上的假設(例如:線性或穩定 ),因此 FAR 模式的適用範圍極為廣泛,更不會因為模式的誤判而導致預測時的嚴重錯誤。最後,我們將 FAR 模式的預測結果與傳統 ARMA 模式做比較。 文中關於模糊時間數列的一些性質,例如:模糊趨勢(fuzzy trend)和模糊穩定(fuzzy stationary),由於傳統文獻中沒有加以討論,本文亦提出定義和新的看法。 / Representations of dynamic data are always different as the time interval or measuring tool change. We call these characteristics of uncertainty fuzziness. But traditional time series use crisp observations to record a fuzzy dynamic process. To completely represent, we consider fuzzy time series replacing the crisp numbers with fuzzy sets and preserve original fuzziness. In this paper, the fuzzy autoregressive model (FAR model) of fuzzy time series is studied and used to forecast the Central government expenditure and exchange rates, respectively. The modeling process is according to Box- Jenkins' (1970) method of ARMA model and merged with the fuzzy set theory proposed by Zadeh (1965). Reasonable human judgements and ways of thinking are taken into consideration throughout the modeling process to make the FAR model more elastic and appropriate for forecasting. Unlike certain incorrectly identified models which lead to inaccurate forecasts, the FAR model can be widely applied due to its not having any assumptions on the original time series (e.g., linearity and stationarity). Finally, the performances of the FAR model to Central government expenditure and exchange rates are compared with that of the traditional ARMA model. Additionally, some properties about fuzzy time series, e.g., fuzzy trend and fuzzy stationary, have not been studied in the literature, and we propose definitions and new opinions.

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