本文主要在探討影響台灣股票市場波動的因素，除了考慮以之前學者設定的 VAR(12)模型研究，另外以 SUR(5)模型來討論股市波動與基本面、交易面間的關係；最後，再以自我迴歸異質條件變異數模型來分析股市波動的特性。最重要的是，我們會根據誤差項的各類檢定結果來判定研究股市波動性質的最佳模型。 在聯立方程式的估計中，我們發現代表資訊到達指標的兩變數--週轉率與成交量成長率--會影響股票市場的波動。另外，我們找出交易面（成交量成長率）可能會影響基本面（匯率），這也就是說，在研究股市波動時，我們不需要特別區分變數的屬性。 在 GARCH 模型及 TGARCH 模型中，我們仍然可發現週轉率與成交量成長率會影響股市條件平均數或條件變異數；除此之外，好壞消息對股市日報酬率條件變異數（條件波動）應有不同的影響效果（壞消息的影響力較快反應）。而股市自身風險係數雖然統計檢定上不顯著異於零，但若未加入條件平均數的估計式，則可能會使模型得到較差的誤差項檢定結果，顯見股市自身風險應為影響投資人設定期望報酬率水準的重要因素之一。 從上述估計結果，我們可以知道，若散戶投資人能正確解讀市場上出現的各種新資訊之背後意義，將可使成交量成長率或週轉率（大部份可能代表無意義或不正確的交易行為）的變動幅度降低，進而有效地減少股票市場中股價異常波動的現象。 / My essay's topic focuses on discussing the factors that influence stock market volatility in Taiwan's stock market. Besides VAR(12) model as previous researchers have studied, I tries to set up SUR(5) models analyzing the relationship among the stock market volatility、the foundamental variables'volatilities and trading activities; Then I cited ARCH models ( autoregressive conditional heteroskedisticity models ) to find out the characteristics of stock market volatility. Most important of all, according to each misspecification test ( residual test ), I would specify the better models to describe the stock market volatility. In the estimations of system equations ( VAR(12)and SUR(5)models ), first I found that turnover rate and the growth rate of trading volume, which represent the information arrival indexes, could effect stock return's monthly conditional variance. Second, I especially found out the evidence that trading activities (trading volume growth) would probably have an impact on the macroeconomic variable ( exchange rate volatility ). It shows that we don't need to distinguish the attributes of those factors which could influence stock market volatility. In GARCH and TGARCH model, the positive influences of turnover and trading volume growth on daily stock return's conditional mean and conditional variance ( conditional volatility ) are still obvious, Within these TGARCH model, I discovered that bad news and good news could have different influences on stock market volatility ( the impact of bad news which resulted in downward movements of stock market volatility appeared faster that the good news'which caused upward movements). Stock market's self-risk(σ_t-1^{^2}) is statistically insignificant different from zero in GARCH models, but when I omitted this variable in daily stock return's conditional mean estimation equation, standardized residual might not obey the assumption of normal distribution. It apparently told us that the stock market's self-risk term ( σ_t-1^{^2} ) is one of the critical factors which influences investors to estimate expected return level. From those results above, we realized that if investors could precisely understand the real meanings of new information conveying in the stock market, it might decrease the levels of turnover and trading volume growth ( which could sometimes represent meaningless or inexact trading activities ), then effectively reduce the abnormal volatility phenomenon in stock market.

本研究主要目的在探討公司宣告海外直接投資，是否會對股東財富有正面的影響，主要透過資本市場上，公司股票價格的漲跌來判斷其影響的方向及程度。研究期間為民國81年到84年，篩選出175筆對外投資宣告的樣本資料，採用事件研究法和市場模式來進行殘差分析，以估算及檢定事件期的平均異常報酬和累積平均異常報酬。此外，由於一些金融性資產如股票、債券、期貨等具有高度變異性的特質，造成殘差項之變異數不再為固定常數，而受上一期異質變異數之影響，且隨時間變動而變動，因此本研究也採用異質條件變異數法(GARCH)來分析。 　　一、總樣本而言 　　公司宣告進行對外直接投資，在宣告日當天股價有顯著為正的顯著異常報酬，股東認為公司進行投資是以公司價值極大化為目標，並能增加股東財富。 　　而本研究也根據不同的統計方法和檢定來比較結果差異，發現T檢定組、Z檢定組、OLS整體樣本組和OLS+GARCH整體樣本組四組所得的實證結果相當一致－異常報酬的變化方向皆相同且宣告日當天的異常報酬都顯著為正。 　　二、一般最小平方法(OLS)和異質條件變異數法之比較 　　本研究接著將72個具有異質變異數特性的樣本，分別以OLS法和GARCH法進行異常報酬的比較，實證結果發現，以OLS法估計具異質變異數的樣本，其平均異常報酬在事件日當天為正，達5%之顯著水準(t=2.459)，而以GARCH法估計的具異質變異數的樣本，其正向異常酬在事件日當天顯著水準為15%(t=1.569)，並不顯著異於零。 　　三、橫斷面複迴歸分析 　　就橫斷面分析結果來看，營業規模和投資東南亞地區達10%的顯著水準能解釋與異常報酬的關係，但呈現負向反應，表營業規模愈大則愈不利於股東財富和投資東南亞並無法增加股東財富。而其他解釋變數則未達顯著水準，其中經營績效、中國大陸地區之迴歸係數符號為正；相對投資金額、獨資之迴歸係數則為負。 　　整體而言，公司從事海外直接投資的宣告，股東都視之為利多消息，顯示海外直接投資對台灣企業的發展和延續有著重要的意義，然而在企業宣告投資後的跨國經營與管理才是台灣企業能否在全球競爭下，成功挑戰廿一世紀的關鍵因素。

學界間廣泛地認為一般金融資產報酬具有的特性是:線型不可預測性,條件 異質變異數,非條件尖峰態 ... 等特性o 固然金融資產報酬具有線型不可 預測之特性,可是並不能否決其間可能有非線型依存關係的存在o目前大部 份經濟計量分析方法中的模式建構問題均是在假設模式的結構訊息已知的 條件下求解,然若真實體系的結構訊息未知或不明朗時,貿然地假設為某種 特定的模式結構,則可能又難於避免模式設定錯誤的困擾,因而對於真實體 系行為的描述亦將可能是誤導且不合理的,這意味著:除非該特定的模式結 構正是真實體系的表徵, 否則無論該特定模式的結構特性多完美,均難以 建構一令人信服的數理化模式來表徵真實體系之行為o 不幸地,此一問題 在高度非線型的動態隨機體系中尤其嚴重, 甚至是否存在一 ``真實'' 模式來據以表徵體系之行為,亦是相當值得懷疑, 故考慮一種無需特定結 構訊息假設的無母數方法或函數逼近法實屬必要o 類神經網路中的倒傳遞 網路模式即是符合此種特性的方法之一o然而學界間仍無法確定的是金融 資產報酬序列資料所產生的 ARCH 效果本身是否為真實序列資料產生機制 特性之顯現, 還是應歸咎於被忽略掉條件均數方面之非線性所衍生模式設 定錯誤情況下的代用模式, 並不得而知;另一方面, ARCH 模式的顯著成就 及其價值亦不能予以輕易地漠視, 因此, 試圖將 ARCH 模式所能提供的攸 關訊息納入倒傳遞網路模式的考量之中而形成倒傳遞網路-自迴歸條件異 質變異數 (BPN-ARCH) 模式以增進樣本外預測能力的精度便是本論文最 主要的嘗試重點與目的o

為瞭解臺灣地區男女自殺死亡率的差異，本文採用Held and Riebler (2010)所建議的多元年齡-年代-世代模型，同時探討男女性自殺死亡率在年齡、年代及世代三種效應上的差異，我們同時使用非條件概似函數法（或稱對數線性模型法）及條件概似函數法（或稱多項式邏輯模型法）對台灣地區男女自殺死亡資料來配適模型。結果發現在假設世代效應與性別無關的前提下，年齡方面， 女性的自殺死亡率在10歲到24歲時顯著比男性高，在15到19歲這個年齡層差異達到最大，20歲之後差異開始變小，到了25至34歲，兩性則已無顯著差異，35歲之後男性的自殺死亡率開始顯著大於女性，並且隨著年齡增長兩性的差異越大，直到60歲之後差異才開始減小，到70歲時兩性無顯著差異。年代方面，男女的自殺死亡率在1959年到1973年間沒有顯著的差異，在1974到1988年女性的自殺死亡率顯著大於男性並於1979年到1983年來到最低點，也就是差異最大，之後差異開始變小，到了1989年時兩性已無顯著差異，從1994年開始男性的自殺死亡率反而開始顯著大於女性，而且隨著年代增加差異越大，並於2004到2008這個年代層差異達到最大。 / To understand the differences in suicide mortality between men and women in Taiwan, this study uses the Multivariate Age-Period-Cohort model proposed by Held and Riebler (2010), and explores the differences in suicide mortality between men and women on age, period and cohort effects adjusted for the other two. We use both unconditional likelihood function method (or log-linear model) and conditional likelihood function method (or multinomial logit model) to fit the model. Assuming that the cohort effect is independent of the gender, female suicide mortality in the age of 10 to 24 years old appears significantly higher than that of male, and the maximum age difference appears at the age of 15 to 19 years old. The difference is getting smaller after the age of 20, and gender difference is no longer significant between age of 25 to 34. After 35-year-old, male suicide death rate starts to exceed that of female, and the difference increases until the age of 60. After 60 years old, the difference starts to decrease till age of 70 at which there is no significant gender differences. There is no significant gender-specific suicide mortality difference between years 1959 and 1973. From 1974 to 1988 female suicide mortality rate is significantly greater than male. The difference reaches the peak in1979 to 1983. After that, the difference is getting smaller, and gender difference is no longer significant between 1989 and 1993. From 1994, suicide mortality for men begins to be significantly greater than women, and the difference increases with period. This difference reaches the maximum level in 2004 to 2008.

於科技發展進步、資訊傳遞方式多樣化之現代生活，因遠距通訊工具問世，即使交易雙方當事人分處兩地亦能締結契約，為消費模式揭開全新一頁。鑑於此一新興交易中，企業經營者單方面提供交易資訊為消費者獲知交易內容的主要方式，容易衍生企業經營者利用對於資訊的壟斷，誘導消費者與之締約，故於消費者保護法中設置「郵購買賣」特別規定予以規範。 惟關於現行郵購買賣定義及效果規範之適用仍存在多項爭議問題與不確定性，有關郵購買賣定義之現存問題，諸如「郵購買賣」用語妥適性如何、郵購買賣適用客體內涵爭論、應否以「未檢視商品」及「買賣契約」作為郵購買賣構成要件；於郵購買賣效果規範部分，對於資訊告知義務履行方式是否須以要式為限，尚無明確規制可供遵循，以及有關無條件解除權猶豫期間之起算方式、無條件解除權適用客體是否合宜等爭點，仍曖昧不明。 其中尤以交易客體多樣化所衍生問題最受矚目，新型態交易客體不同於過去傳統實體商品，軟體設計、數位化商品、新興服務等軟實力，已然成為台灣躍居世界舞台不可或缺要素，然尚欠周延之消費者保護法規可能扼殺此等新興交易客體發展空間，譬如對於本質上具有「無限複製」與「完整複製」特性之數位化商品行使無條件解除權者，縱該數位化商品附有反複製技術，仍無法完全排除該反複製技術遭受破解之可能；又如消費者針對通常於締約後即履行之服務主張不附理由解除契約之際，亦因服務所具無法回復原狀性質，將致消費者接受全部服務後卻不必支付價金之結果，實則前述事例於現行法規範下，企業經營者所負經營管理成本已然失控。 是以，揆諸郵購買賣所具特殊交易性質、交易客體複雜化等背景，與現行郵購買賣規範交錯致生問題引發筆者研究興趣，並以之成為本文撰寫起點，同時祈能藉由本文就郵購買賣構成要件與效果規範相關問題之發覺，及援引參照日本消費者保護法規內容，由法制面之檢討著手，釐清各項爭議原委，探尋法規範更為整備之修正可能性與方向，以彰消費安全保障之目的。

本篇文章將採用長期記憶模型之一的HYGARCH模型，搭配1985年廣場協議後的日圓匯率期貨資料來估計日圓期貨匯率買入和放空部位的日報酬風險值，探討控管日圓匯率期貨在使用上的風險。為了更準確地計算風險值，本文採用常態分配、學生t分配以及偏態學生t分配來作模型估計以及風險值之計算。 本文實證的結果將有兩方面的貢獻：首先，實證結果顯示當我們採用厚尾分配估計風險值時，樣本內風險值的估計誤差會與信賴水準的高低呈正比的現象，證明在極端的風險值估計上，厚尾分配均有較佳的表現。其次，與其他使用HYGARCH模型研究日圓匯率的文章相較，本文在風險控管層面上所提供的偏態學生t分配，於估計風險值時，比起只考慮厚尾的對稱學生t分配將來得更為有效，其不但在估計誤差上較小，而且根據Kupiec檢定法，其在樣本內的風險值估計也有較好的表現。此外，本文也將多方證明此資料的偏態分配屬於右偏。 / In order to manage the exposure of the dollar/yen futures returns with regarding the long memory behavior in volatility, we use the HYGARCH(1,d,1) model with the data after the Plaza Accord to compute daily Value-at-Risk (VaR) of long and short trading positions. To take into account the fat-tail situation in financial time series, we estimate the model under the normal, Student-t, and skewed Student-t distributions. The contribution of this article is twofold. First, the empirical results show that the bias of in-sample VaR increases as the confidence level increases when VaR is calculated with a fat-tail distribution. Second, we provide a better distribution, the skewed Student-t innovation, for estimating the HYGARCH model for the Japanese yen in respect of risk management because the bias under the skewed Student-t innovation is smaller than that under the Student-t distribution, and in-sample VaR of the models with a skewed Student-t distribution outperforms based on Kupiec test. In addition, we get the innovation skewed to the right through the in-sample VaR analysis.

本文的主旨在評價二次擔保債權憑證。在條件獨立機率的假設下，我們使用factor copula的方法去刻劃違約事件間的相關係數，並提供了一個有效率的迴圈演算法去建構損失分配。本方法同時考慮違約數目及違約位置，同時亦可解決重疊性的問題。本文所建構的是Hull and White(2004)的延申模型。我們也對各參數作敏感度分析，以求得其對分券價差的影響。文中亦主張一些風險衝量指標，以量化重疊性的程度等風險議題。 / In this paper we address the pricing issues of CDO of CDOs. Underlying the conditional indepdence assumption we use the factor copula approach to characterize the correlation of defaults events. We provide an efficient recursive algorithm that constructs the loss distribution. Our algorithm accounts for the number of defaults, the location of defaults among inner CDOs, and in addition the degree of overlapping between inner CDOs. Our algorithm is a natural extension of the probability bucketing method of Hull and White (2004). We analyze the sensitivity of different parameters on the tranche spreads of a CDO-squared, and in order to characterize the risk-reward profiles of CDO-squared tranches, we introduces appropriate risk measures that quantify the degree of overlapping among the inner CDOs. Hull and White (2004) presents a recursive scheme known as probability bucketing approach to construct conditional loss distribution of CDO. However, this approach is insufficient to capture the complexities of CDO². In the case of the modeling of CDO, we are concerned for the probabilities of different number of defaults upon a time horizon t, e.g., the probabilities of 3 defaults happened within a year. With the mentioned probabilities, we can then calculate the expected loss within the time horizon, which enables us to figure out the spreads of CDO. However, in the modeling of CDO², an appropriate valuation should be able to overcome two more difficulties: (1) the overlapping structure of the underlying CDOs, and (2) the location where defaults happened, in order to get the fair spreads of CDO².

我國緩起訴制度於2002 年制定，立法者於立法時已明文緩起訴係立基於訴訟經濟之目的，以及預防被告再犯之特別預防之刑事政策為出發。而緩起訴制度自2002 年施行至今約莫13 年，是否確能落實當年立法者所預期達成之目的，有效達成被告再犯預防之特別預防目的？或反而因為附條件緩起訴存在太過便利，附條件緩起訴之相關指示與負擔選擇多元且包羅萬象，而忽視制度本身原應該追求的目的？對於制度之目的產生問題後，因我國立法時參考的外國法制為日本的起訴猶豫制度，在日本法上起訴猶豫制度之運用是否也有類似的問題？而因緩起訴制度為一種刑事政策之轉向處分，美國法制上亦有性質類似的審前轉向原則，是否有得以參考的地方？所謂「他山之石，可以攻錯」，若想要達成緩起訴預防再犯之功能，以外國法制作為借鏡下，有無可提供我國法制得以參考的地方？在這樣的思考脈絡下，最後提出本文的一點想法以及參考。 本文希望藉由檢討目前實務上緩起訴之運作狀況，以預防被告再犯之立法初衷為著力點，探討在現行法制下附條件緩起訴之應然面與實然面之落差，並以外國法制作為借鏡，提出緩起訴制度重新思考的方向與建議。期使未來實務上檢察官在作成附條件緩起訴處分時，能夠從預防被告再犯的角度出發，思考附條件緩起訴「應該」要達到怎樣的效果，並藉由參考外國法制之程序上配套措施，相關配套之引進必要性與可能性之探討，希冀附條件緩起訴能夠發揮達到預被被告再犯之目的與效果。

設二個隨機變數X1 和X2，所可能的發生值分別為{1,…,I}和{1,…,J}。條件機率分配模型為二個I × J 的矩陣A 和B，分別代表在X2 給定的條件下X1的條件機率分配和在X1 給定的條件下X2的條件機率分配。若存在一個聯合機率分配，而且它的二個條件機率分配剛好就是A 和B，則稱A和B相容。我們透過圖形表示法，提出新的二個離散條件機率分配會相容的充分必要條件。另外，我們證明，二個相容的條件機率分配會有唯一的聯合機率分配的充分必要條件為:所對應的圖形是相連的。我們也討論馬可夫鏈與相容性的關係。 / For two discrete random variables X1 and X2 taking values in {1,…,I} and {1,…,J}, respectively, a putative conditional model for the joint distribution of X1 and X2 consists of two I × J matrices representing the conditional distributions of X1 given X2 and of X2 given X1. We say that two conditional distributions (matrices) A and B are compatible if there exists a joint distribution of X1 and X2 whose two conditional distributions are exactly A and B. We present new versions of necessary and sufficient conditions for compatibility of discrete conditional distributions via a graphical representation. Moreover, we show that there is a unique joint distribution for two given compatible conditional distributions if and only if the corresponding graph is connected. Markov chain characterizations are also presented.

80年代，我國在解嚴之時，民主化運動與言論自由的保障相得益彰，幾乎同一時期，司法院大法官作成釋字第187號解釋，對於特別權力關係敲響第一記警鐘，大法官逐步正視特別權力關係理論對於權利保障與憲政制度的影響，在司法實踐上似乎邁向突破特別權力關係理論長久以來的桎梏。然探其實際，在大法官與學者相繼對於特別權力關係理論加以解構後，公務員仍未能如同民主化後的一般人民一樣享有「充分且必要」的言論自由。 在面對公務員言論爭議的案件中，我國現行法制透過概括的職務義務對於公務員言論自由施加限制。在具體個案的審查中，實務上顯然並不認為公務員享有與一般人民相同的言論自由，就公務員言論應有的界限與限制的標準，也未建立可茲遵循的審查原則。造成此一現象的原因或許在於特別權力關係尚未真正地被揚棄，學者與實務對於公務員「有權利即有救濟」的闡述，過於囿限於「服公職權」，並且在檢討、揚棄特別權力關係的過程中，仍停留在形式法治國的概念，忽略了基本權利實質限制的檢討。 本文借鏡美國法制的發展，嘗試為我國公務員言論自由的審查提出基本原則。在衡量公務員言論自由保障時，應考量「公務員言論的類型」與「公務員的職務內容」，並以「言論表達的時間與地點」與「言論的公開程度」作為輔助判斷因素，衡酌公務員言論對於政府制度目的的影響。在此一審查模型下，並非所有的公務員言論皆受到一致的限制。 法哲學家Dworkin教授曾經說過，在言論自由的困難案件中，法律人必然需要釐清「憲法為何保障言論自由」這個根本性的問題，才能決定言論自由的困難案件應該如何解決。期待本文的觀察建議可以使得實務在審查公務員言論自由的案件時，意識到公務員言論可能具有的公益面向—使政府資訊自由地流向公眾，促進政府課責與民主審議—從而能夠適當的權衡相關利益，賦予公務員言論應有的保障。 / In the 1980s, as the Martial law was lifted, the level of freedom of speech enjoyed by the people was increased alongside with Taiwan’s democratization movement. In the same period, the Constitutional Court rendered the landmark Interpretation No.187 against the theory of special power relation (besonderes Gewaltverhaltnis, the Theory). The Court was concerned with the negative effect of the Theory on constitutionally protected rights and liberties. However, even though the Court had since made several similar interpretations and seemed to gradually move toward abandoning the Theory entirely, Taiwan’s public employees have not yet been able to enjoy the same level of freedom of speech as the general public has. Under the current legal system, civil servants’ freedom of speech was restricted by broad and generalized professional duties specified in the Public Functionary Service Act. In addition, courts do not take the view that public employees and the general public enjoy the same level of freedom of expression, and do not establish a clear principle to determine what public employees can or cannot speak. Perhaps it is because the Theory has lingered on. Or it is because in the process of abandoning the Theory, courts have paid too much attention on the right to holding public offices and ignored other rights, such as the right to free speech. Learning from the public employee speech jurisprudence in the United States, this thesis tries to articulate some basic principles when reviewing cases concerning civil servants’ freedom of speech. This thesis believes that not all public employee speech should be restricted and suppressed. In deciding whether to protect civil servants’ freedom of expression, courts should consider two main factors: “the type of the speech involved” and “the responsibilities of the civil servant’s position.” In addition, factors such as “the time and place of the speech” and “degree of openness of the speech” should also be taken into account when deciding whether public employee speech has negative impact on the government in fulfilling its responsibilities. Professor Ronald Dworkin, an American legal philosopher, once remarked that in hard cases, “lawyers and judges must try to find a political justification of the First Amendment that fits most past constitutional practice and also provides a compelling reason why we should grant freedom of speech.” The thesis hopes that the observation and suggestion made in this research can help courts be aware of the public interests in protecting public employees’ freedom of speech—ensuring free flow of information from the government to the public and improving government accountability and democratic deliberation. Then can the courts better balance the relevant interests and ultimately afford proper protection to public employee speech.