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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.
631

企業購併與總體經濟波動之研究 :非恆定性時間數列計量方法之研究

鄭旭凱 Unknown Date (has links)
本文利用晚近發展出來的單根檢定法以及共積檢定法,實証分析美、日兩國二次大戰以後企業購併與總體經濟變數間之關係。其實証方法與實証結果如下:運用ADF 檢定方法對購併、股價、國民生產毛額、利率,作單根檢定,發現美日兩國之購併、股價與國民生產毛額呈一階差分恆定狀態。 此外,本文應用Engle and Granger(1987) 的共積模型分析,將同樣為一 階差分恆定的變數做共積檢定,發現美日兩國之購併與股價、國民生產之間,皆具有長期共同移動的趨勢,因此可以建立一包含長、短期關係之誤差修正模型。本文之實証結果顯示:美國的企業購併與股價水準有正向且顯著之長期穩定關係,而與國民生產毛額則有負向且顯著的長期穩定關係;日本的企業購併與股價及國民生產毛額也有長期穩定之關係,惟影響方向與美國相反。另外,因果關係檢定結果顯示,美國之股價與利率對購併呈單向因果關係,而日本之股價與購併則呈雙向因果關係。由這些實証結果可知,購併風潮之形成,實肇因於總體經濟之波動,而不同國家之企業,由於法令規章、經濟結構、社會制度之不同,因而會有不同之反應。
632

投資模型之建構以因應退休基金之投資避險策略 / A Study of Model Building in Investment Hedging Strategy of Pension Fund

黃彥富 Unknown Date (has links)
本研究的目的是針對退休金的長期負債以資產負債管理的方式提出有效的投資避險策略建議。在過去,傳統精算的資產負債管理大多採用確定投資模型(Deterministic Model),即以過去的經驗設立「精算假設」,但是這樣的假設無法精確的呈現未來的趨勢,所以本文的第一部份,便是根據過去的台灣總體經濟資料,建構一個退休基金的隨機投資模型(Stochastic Investment Model)。首先,我們以ECM(Error Correlation Model)模式建構出第一個投資模型,之後在精簡參數的考量下,建構第二個以因果關係為基礎的Causality投資模型,再以模型配適能力與預測能力比較兩模型,結果顯示Causality投資模型優於ECM投資模型。   有了投資模型,我們設定不同的退休金負債形式,如固定成長型負債MF、隨通貨膨脹成長M<sup>R</sup>負債及隨max{固定成長比例,通貨膨脹}而成長的退休金負債M<sup>L</sup>,以靜態避險的方式去求得各資產的最適配適比例。從模擬的結果中發現隨著到期日的增長,投資在風險性高報酬率佳的投資標的物上的比例也越來越高。另外,隨著負債固定成長比例f的增加,其M<sup>L</sup>負債之期初資產配置額便越接近M<sup>F</sup>負債之期初資產配置額。整體而言,我們由模擬中可得出,使用投資組合的投資方式優於單一資產投資的結論。 / In this study, we investigate the hedging strategies for pension liabilities by using Asset-Liability Management method. In the past, the traditional actuarial valuation usually does not take account of market value for both assets and liabilities. Most of the traditional actuarial valuation adopted the Deterministic Model, that is, setting the assumptions based on the experiences. However, it can not exactly show the trend in the future. In part one of this study, we build a stochastic investment model for the pension funds based on Taiwan Market data. First, we apply the first model : ECM( Error Correlation Model ). And then, we apply the second model : Causality Model under considering parsimonious parameterization. Finally, we compare the results of ECM with Causality Model on fitting and forecasting efficiency, and we find that Causality Model is better than ECM. With the investment model, we set some formulas of pension liabilities calculated to obtain the best fit proportion of each valuation by the static hedging. This involves finding optimal static hedging strategies to minimize riskiness of the investment portfolio relative to the liability. Overall, from the simulation results, for static hedging in these kinds of liabilities, investing in all three assets is a better strategy than investing in a single asset class. This confirms that the more assets we use, the more effectively we can hedge.
633

原物料指數與總經物價指數關聯性分析 / The analysis of the relationship between commodity price index and macroeconomic price indexes

謝濱宇 Unknown Date (has links)
本篇主要為原物料指數與總體經濟物價間動態關聯性的研究。由於近年來糧食價格高漲,本研究選取CRB現貨指數(Commodity Research Bureau)、CCI期貨指數(Continuous Commodity Index),與CRB農產品指數為原物料指數以觀察原物料價格對總體面物價影響的程度;研究期間為2001年10月至2011年3月;總經物價指標選擇生產者物價指數(PPI)、消費者物價指數(CPI)、再加上國內生產毛額(GDP);選取的國家為美國、臺灣與中國。本研究以Johansen共整合、向量自我迴歸模型、向量誤差修正模型、Granger因果關係檢定及衝擊反應分析等方法,探討三項原物料指數與總體經濟指標的互動關係。 研究結果顯示,原物料指數與總體指標之間的長期均衡關係不明顯。因果檢定顯示,CCI指數在因果檢定上領先CRB指數與CRB農產品指數;除了美國的GDP之外,CCI指數也領先各項總體經濟指標,但不論是CRB現貨指數或CRB農產品指數,對總經物價指標的領先-落後關係都不明顯,表示在CCI指數為較佳的預測指標。由衝擊反應分析的結果顯示,除了有共整合關係的變數間相互影響為長期性之外,受影響的物價指標僅在短期內會受到原物料價格變動的影響:總體物價指標面對原物料價格波動的反應約3期之後反應便逐漸消失,顯示原物料價格與總體物價指數之間的短期失衡期間並不長。 / This paper investigates the relationship between the commodity indexes and macroeconomic price indexes. Due to the sharp increase of food price in recent years, we add CRB index (Commodity Research Bureau), CCI index (Continuous Commodity Index), and CRB foodstuffs index in the research to see the magnitude of commodity price indexes to macroeconomic price indexes. This paper selects United State, Taiwan and China as samples and manages to find out the relationship of commodity indexes and macroeconomic price indexes by applying monthly data from October 2001 to March 2011. Macroeconomic price indexes are PPI (Producer Price Index), CPI( Consumer Price Index) and plus GDP Index. This paper tries to get the answer by applying Johansen Cointegration Test, Vector Autoregression Model(VAR), Vector Error Correction Model (VECM), Granger causality test and Impulse Response Analysis. The result does not show obvious long-term relationship between commodity price indexes and macroeconomic price indexes; and Granger causality test exhibits that CCI index takes the lead in the change of time. But we do not get consistent result between CRB index, CRB foodstuffs index and macroeconomic price indexes in Granger causality test which means commodity spot indexes do not necessarily lead in the change of time. This result implies that CCI index a better indicator in forecasting. According to Impulse Response Analysis, macroeconomic price indexes are influenced by commodity index only in a short period of time and this result tells us that the disequilibrium between commodity indexes and macroeconomic price indexes will not last long.
634

Epidemiological Aspects of Asthma in Primary Care : Special Reference to Prevalence, Clinical Detection and Validation

Hasselgren, Mikael January 2005 (has links)
<p>Objectives. To describe the prevalence of asthma in a mid-Swedish region and measure the detection rate of asthma in primary care. To compare clinical outcomes for adolescents with asthma in primary care or in paediatric care and to perform a clinical validation in children with airway, nose and skin symptoms.</p><p>Material and methods. A questionnaire survey of respiratory symptoms and disease in an adult population and an investigation of the occurrence of clinically detected asthma in primary care. A cross-sectional study comparing management, asthma control and quality of life in adolescents. The last study was a nested case-control study with a clinical validation of reported allergic symptoms in children.</p><p>Results. The prevalence of asthma in the adult population was 8%. The clinical prevalence of asthma in primary care was 2%. The detection rate was higher in primary health care centres with asthma clinics, as compared to primary care without such clinics. In adolescents with asthma there was no difference in clinical outcomes between primary care and paediatric care. The validation study showed a high correlation between assigned cases and disease. </p><p>Conclusions. Asthma is a common disease where the majority of cases are managed in primary care. Many cases are, however, not diagnosed and the detection rate becomes a quality care indicator. The study of adolescents confirms that proactive care can be further improved regardless of whether their management is in primary or paediatric care. The nested case-control design is suitable to suggest causational risk factors for asthma and for prediction of allergic disease development.</p>
635

Explanation and deduction : a defence of deductive chauvinism

Hållsten, Henrik January 2001 (has links)
In this essay I defend the notion of deductive explanation mainly against two types of putative counterexamples: those found in genuinely indeterministic systems and those found in complex dynamic systems. Using Railton's notions of explanatory information and ideal explanatory text, deductivism is defended in an indeterministic setting. Furthermore, an argument against non-deductivism that hinges on peculiarities of probabilistic causality is presented. The use of the notion of an ideal explanatory text gives rise to problems in accounting for explanations in complex dynamic systems, regardless of whether they are deterministic or not. These problems are considered in the essay and a solution is suggested. This solution forces the deductivist to abandon the requirement that an explanation consists of a deductive argument, but it is argued that the core of deductivism is saved in so far as we, for full explanations, can still adhere to the fundamental requirement: If A explains B, then A is inconsistent with anything inconsistent with B.
636

兩岸三地股價指數期貨連動性之研究 / The Study of Relationship among The Stock Index Futures in Taiwan, China and Hong Kong

蕭宥榛 Unknown Date (has links)
本篇探討在2010年4月16日滬深300股指期貨正式上市到2012年9月18日止的連續近月每日收盤日資料,進行區域內金融期貨市場連動關係的研究,試圖發現兩岸三地之股價指數期貨市場在亞太地區的金融主導地位,以作為國內外投資者在區域內的投資決策參考。 實證結果顯示,從共整合及向量誤差修正模型檢定發現,兩岸三地股指期貨具有長期均衡及短期的互動關係,因此可以視此三地為單一區域市場。在Granger因果檢定上,台股指數期貨雖無法預測恆生指數期貨,但仍明顯領先滬深300股指期貨且程度大於恆生指數期貨,或可推測兩岸因ECFA的簽訂使實體經濟的關聯性更為緊密,至於恆生指數期貨大多以金融、地產股為其主要成分,與大陸主要以實體經濟為主的金融市場,其Granger預測滬深300股指期貨的能力因此相對較弱。另由衝擊反應檢定得知恆生指數期貨為一獨立的市場,不受台灣及大陸指數期貨市場衝擊的影響;滬深300指數期貨因大陸金融市場逐漸開放,也會受到香港及台灣金融期貨市場之衝擊而產生影響;至於台股指數期貨則在兩岸三地,最易受到其他市場影響。最後由預測變異數分解檢定發現,台股指數期貨及滬深300股指期貨的波動皆易受到恆生股價指數期貨變異的影響,而恆生指數期貨在兩岸三地間之解釋能力最強,於兩岸三地間具金融主導地位。至於台股指數期貨對大陸金融期貨的影響也有突出的表現,因此若政府有心推展亞太金融中心之營運,勢必得加強區域間整合的力度,提出有利吸引外資之最政策,以增加台灣股市於國際間之競爭力。 / This study conducts analysis of regional linkage between financial futures market by examining consecutive daily closing information from April 16, 2010 (the official list date of CSI 300 index futures) to September 18, 2012. This study tries to find the financial dominance of these index futures market in the Asia Pacific region and hopefully it may be used as an investment decision reference for domestic and foreign investors. The empirical results show that from the total integration and vector error correction model tests and three places all indicate long-run equilibrium stock index futures and short-term interaction. Therefore, these three places can be viewed as a single regional market. In the Granger causality test on the TAIEX futures and Hang Seng Index futures, in spite of TAIEX futures can’t predict Hang Seng Index futures, it is significantly ahead of the CSI 300 index futures. TAIEX futures on the CSI 300 index futures even more impact than the Hang Seng Index Futures. It can explain that the ECFA has been signed and results show closely-related economy. Since the Hang Seng Index futures are mainly from financial and real estate stocks while the mainland-based financial market is mainly from the real economy, Granger predicts ability of CSI 300 index futures is relatively weak. Another test on the impulse response shows that (1) Hang Seng Index Futures is an independent market and is not affected by shocks from Taiwan and the mainland index futures markets, (2) CSI 300 index futures is affected by shocks from Hong Kong and Taiwan because of the gradually open financial markets, and (3) TAIEX futures can be seen as a potential Taiwanese dish economy because it is most vulnerable to other market influences among the three places. To sum up, the forecast variance decomposition tests show that TAIEX futures and the CSI 300 stock index futures are vulnerable to fluctuations in the Hang Seng index futures. In order words, the Hang Seng Index futures have the strongest explanatory power among the three places and shows financial dominance. The TAIEX futures also show its significant impact on the mainland China financial futures index. If the Government decides to promote the operation of the Asia-Pacific financial center and to increase competitiveness of Taiwan stock market, it will inevitably have to strengthen inter-regional integration efforts and make the most favorable policies to attract foreign investment.
637

Calculating control variables with age at onset data to adjust for conditions prior to exposure

Höfler, Michael, Brueck, Tanja, Lieb, Roselind, Wittchen, Hans-Ulrich 20 February 2013 (has links) (PDF)
Background: When assessing the association between a factor X and a subsequent outcome Y in observational studies, the question that arises is what are the variables to adjust for to reduce bias due to confounding for causal inference on the effect of X on Y. Disregarding such factors is often a source of overestimation because these variables may affect both X and Y. On the other hand, adjustment for such variables can also be a source of underestimation because such variables may be the causal consequence of X and part of the mechanism that leads from X to Y. Methods: In this paper, we present a simple method to compute control variables in the presence of age at onset data on both X and a set of other variables. Using these age at onset data, control variables are computed that adjust only for conditions that occur prior to X. This strategy can be used in prospective as well as in survival analysis. Our method is motivated by an argument based on the counterfactual model of a causal effect. Results: The procedure is exemplified by examining of the relation between panic attack and the subsequent incidence of MDD. Conclusions: The results reveal that the adjustment for all other variables, irrespective of their temporal relation to X, can yield a false negative result (despite unconsidered confounders and other sources of bias).
638

台灣婦女教育程度與龍虎年效應對生育率之影響 / The Influence of Female Education and the Chinese Animal Zodiac on Fertility Rate in Taiwan

黃修梅, Huang, Hsiu-Mei Unknown Date (has links)
本文的主要研究目的,在於將文化因素(即龍年與虎年效果)納入生育行為的考量,以重新審視台灣生育率與婦女教育程度之間的Granger因果關係。利用台灣1952年至1994年資料進行實證的Cheng and Nwachukwu(1997)及Cheng(1999),其結論指出台灣教育程度與生育率之Granger因果關係並不顯著。本文將以該文章之實證模型為基礎,並加入代表龍年效應與虎年效應的虛擬變數以建立本文模型。 首先根據Cheng(1999)的資料與變數,利用台灣1952年至2005年之年資料,建立一個包含粗出生率、教育程度大專以上的比例、女性勞動參與率、與實質經濟成長率等四個內生變數,以及代表龍虎年效應的兩個虛擬變數之VAR模型。並以Toda and Yamamoto(1995)提出的Granger因果關係檢定,檢定台灣教育程度與生育率之間的因果關係。隨後,為增進估計的有效性,本文利用台灣地區1978年至2005年的季資料,共112個樣本進行實證研究。變數定義方面,將粗出生率替換為一般生育率,教育程度大專以上的比例替換為育齡婦女大專以上的比例。並根據上述建立之VAR模型,進行Granger因果關係檢定。 經由本文的實證研究發現,將龍年效果與虎年效果納入考量後,台灣婦女教育程度的提昇會Granger影響生育率的下降。亦即台灣婦女教育程度日益提升,是解釋生育率下降的重要因素,此結果與Cheng(1999)所提出的結果並不一致。此外,龍年與虎年對台灣的生育率分別有顯著正向與負向的影響。 / This paper tries to revisit the null hypothesis of Granger no-causality between female education and fertility rate in Taiwan, by considering the culture factors captured by Dragon and Tiger Years which might influences the fertility behavior. In addition, this study compares the primary finding with the result proposed by Cheng and Nwachukwu (1997) and Cheng (1999) which are that female education does not affect fertility rate in Taiwan. According to Cheng (1999), official time series yearly data from 1952 to 2005 provided by Taiwan government are used first, and quarterly data from 1978 to 2005 are required to improve the efficiency. This study models a 4-Variables VAR and applies Granger no-causality test proposed by Toda and Yamamoto (1995). The primary finding of this study is that there is a negative causality from female education to fertility rate in Taiwan, which is inconsistent with conclusions in Cheng (1999). In addition, culture factors do play a very important role in fertility behavior in Taiwan.
639

Divine causality and human free choice : Domingo Báñez and the Controversy de Auxiliis

Matava, Robert Joseph January 2010 (has links)
This dissertation considers the mystery of the relationship between human free choice and God by focusing on the Controversy de Auxiliis (1582-1607) and the thought of Domingo Báñez, O.P. (1528-1604) in particular. The dissertation comprises four chapters and a conclusion preceded by a preface and brief historical introduction. The preface introduces the issue to be explored and the motivations for exploring it before providing a general synopsis of the dissertation that is more detailed than the present abstract. The historical summary that follows introduces a theological debate that has become widely unfamiliar to contemporary theology, even while conceptually, that debate remains perennial. The four-chapter body that follows may be divided into two general parts: Broadly, chapters One and Two exposit Báñez’s thought, while chapters Three and Four critique it. Chapter One explores Báñez’s positive account of physical premotion, human freedom and sin. Chapter Two examines Báñez’s critique of Luis de Molina S.J.’s alternative proposal, in conjunction with some contemporary sources from both sides of the debate (Molina was Báñez’s principal adversary in the Controversy de Auxiliis). Báñez’s line of critique in Chapter Two is found to be cogent. Chapter Three investigates Molina’s critique of Báñez and finds it too to be cogent, even though Molina’s positive account was found to be problematic in Chapter Two. Chapter Four begins by exploring Bernard Lonergan S.J.’s work on divine causality and human free choice. Lonergan attempts to provide a fresh historical reading of Aquinas that is unencumbered by the presuppositions of the Controversy de Auxiliis. The first part of Chapter Four explains Lonergan’s critique of Báñez and finds it convincing, while the second part of the chapter finds Lonergan’s interpretation of Aquinas problematic from a theoretical standpoint. Chapter Four then offers a constructive critique of Lonergan’s interpretation before advancing an alternative way to think about God’s causation of human free choices. In closing, this dissertation argues that God creates human free choices, but that in creating a human free choice, God, or God’s creative will, is not an antecedent condition that determines choice. Rather, God creates the entire reality of a human free choice—both what it is and that it is—and in so doing, part of the reality God creates just is that choice’s being up to its human agent.
640

Μελέτη της σχέσης μεταξύ δείκτη εμπιστοσύνης του καταναλωτή και χρηματιστηριακών αποδόσεων στα ευρωπαϊκά χρηματιστήρια

Πάκου, Αντωνία 07 January 2009 (has links)
Στην παρούσα εργασία μελετούμε τη σχέση μεταξύ χρηματιστηριακών αποδόσεων και δείκτη εμπιστοσύνης στις 27 χώρες-μέλη της ΕΕ για τα έτη 1985-2006. Βρήκαμε ότι για το μεγαλύτερο μέρος των χωρών της ΕΕ εμφανίζεται θετική συσχέτιση μεταξύ αποδόσεων και δείκτη εμπιστοσύνης του καταναλωτή στον βραχυχρόνιο ορίζοντα. Οι μεταβολές και στους δύο δείκτες τείνουν να κινούνται παράλληλα στην ίδια περίοδο, με εξαίρεση την πλειοψηφία των νεοεισελθέντων χωρών. Στον μακροπρόθεσμο ορίζοντα, βρήκαμε ότι για τις περισσότερες χώρες ο συντελεστής γίνεται σχεδόν μηδενικός. Για το μεγαλύτερο μέρος των χωρών της ΕΕ υφίσταται σχέση αιτιότητας μεταξύ των μεταβλητών, με τις αποδόσεις να προκαλούν κατά Granger τον δείκτη εμπιστοσύνης του καταναλωτή και τον δείκτη οικονομικής εμπιστοσύνης, αλλά το αντίστροφο δεν ισχύει. Αμφίδρομη σχέση αιτιότητας μεταξύ αποδόσεων και εμπιστοσύνης των καταναλωτών παρατηρείται μόνο για την Γαλλία οριακά, ενώ για την ΕΕ βρήκαμε οτι υπάρχει αμφίδρομη σχέση αιτιότητας μεταξύ αποδόσεων και δείκτη οικονομικής εμπιστoσύνης. / This paper studies the relationship between stock market developments and confidence index for the 27 EU countries - members over the years 1985-2006. We found that for the majority of the EU countries exists positive correlation between the stock market index and the confidence indicators (consumer confidence indicator and economic sentiment indicator) in the short horizon. The changes between these indexes tempt to move in the same direction contemporaneously and in the short horizon (of 1 month), with the new EU members to be an exception. The correlation becomes almost zero in the long horizon. For the most of the EU countries there is causality between the variables. Stock returns in general Granger-cause the Consumer Confidence Index and the Economic Sentiment Indicator, but not vice versa. We found also that there is feedback causality relationship between stock returns and confidence for France and the EU as a whole.

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