本文首先構建了在完全資訊下的異質分群模型。當玩家可以觀察其他玩家的類型，則均衡必定是非隔離的：大多數玩家將無意移動，這是因為他們的夥伴可以為他們帶來最好的報酬。均衡狀態將會是一個有效率的狀態。     然後，我們構建另一個分組模型:訊息不完全和雙重改變下的分群模型。結果表明，雖然非隔離的均衡有可能是在短期的穩定均衡，但只有隔離的均衡狀態可以在長期維持穩定。這是因為在長期下，大多數非隔離狀態可以輕易地切換到隔離狀態的緣故。 / This paper first constructs a grouping model with heterogeneous population under the setting of complete information. When player can observe other's type, the result isnon-segregation: most players have no intention to move and they can match with the one who brings them the best payoff in the original group. The equilibrium state is always efficient. We then construct another grouping model with incomplete information and double mutation. The result shows that, although non-segregation equilibria may emerge as stable equilibria in the short run, only segregation equilibria can be stochastically stable in the long run. This is because most of non-segregated states can switch to the others by the same re-sistance and some of them can easily switch to segregated state, but it is hard to switch back.

本研究建立含資產價格泡沫的隨機動態一般均衡 (Dynamic Stochastic General Equilibrium, DSGE) 模型，並以此討論貨幣政策與總體審慎政策的效果。泡沫存在於不動產的股票價格上，且不動產與一般資本皆為生產要素。研究顯示，在隨機衝擊下，一般資本的投資與不動產投資呈現負相關。融資擔保率的調控為總體審慎政策的範疇，本文另研究融資擔保率對經濟變數的影響。結果顯示，當擔保率調升時，產出增加、泡沫減少且不動產的股價 (資產價格) 下跌。本文亦討論依循泰勒法則下的貨幣政策與總體審慎政策對產出與資產價格波動的影響；結果顯示，在經濟景氣時實施緊縮貨幣政策可同時減少資產價格與產出的波動，其效果優於總體審慎政策。 / This study established a Dynamic Stochastic General Equilibrium (DSGE) model, which contains asset bubble price, and employed DSGE to discuss the effect of the monetary policy and the macro-prudential policy. Bubbles exist in the stock price of the real estate. Real estate and general capital are both the factors of production. The study indicates that, under stochastic impulse, a negative correlation exists between the investment of the general capital and the investment of the real estate. The study also discusses the operation of the collateral rate, a perspective dealing with macro-prudential policy, and how it influences economic variables. The results present that when collateral rate rises, output increases, bubbles decreases and the stock price of real estate (asset price) declines. The study further investigates how monetary policy, which follows the Taylor rule, and macro-prudential policy affect the vibration of the output and the asset price. The result indicates that during economic prosperity, the implementation of tight monetary policy presents better effect than that of macro-prudential policy since it simultaneously decreases variances of output and asset price.

從2015年統計數據來看，中國大陸涉農金融機構地方滲透性比重較高。03年中國大陸國務院下發《深化農村信用社改革試點方案》到現在為止雖然14年了，但是農村信用社還是存在很多問題。 所以研究農村信用社經營效率，對提高涉農金融機構質量和促進中國大陸農村金融市場的發展具有重大的意義。 本研究以數據包絡分析法為主，由於dea方法沒有考慮到誤差項的分配，因此加入了隨機前沿分析法。 本研究發現雖有個別農村信用社效率不足的情況存在，但福建地區整體農村信用社各項指標都很穩定。只是要針對個別經濟環境不景氣的地區重點研究，造成其效率低下的主要原因，改善其經營效率，也能提高整體指標。 從本研究對福建省地區農村信用社效率的比較影射到全國農村信用社。在國務院對農村金融改革後，雖農信社還存在部分問題，但也慢慢趨向穩定發展。可看出國務院的金融改革日漸成效。 / The statistical data of 2015 indicates that most of the Chinese local financial institutions are served as agriculture-related financial institutions.Although state council promulgated<The reform of rural credit cooperatives >in 2003, there are still lots of problems to be solved today. Therefore, the researches about the operating efficiency of rural credit cooperatives can help not only the improvement in the quality of agriculture-related financial institutions but also the development of rural financial market in China. This paper is mainly based on the data envelop analysis (DEA). Because the DEA doesn't consider the distribution of residuals, we also use the stochastic frontier analysis. In this paper, we find that the inefficiency problem still exists in some rural credit cooperatives, but all indexes of overall rural credit cooperatives in Fujian area are still stable. Moreover, we think that the improvement in the operating efficiency of individual rural credit cooperatives can also improve the overall indexes. Applying our analysis into whole districts of China, we find that the development becomes stable gradually, meaning the reform by state council works.

本研究以Lévy過程為模型基礎，考慮Merton Jump及跳躍強度服從Hawkes Process的Merton Jump兩種跳躍風險，利用Particle Filter方法及EM演算法估計出模型參數並計算出對數概似值、AIC及BIC。以S&P500指數為實證資料，比較隨機波動度模型、Variance Gamma模型及兩種不同跳躍風險對市場真實價格的配適效果。實證結果顯示，隨機波動度模型其配適效果勝於Variance Gamma模型，且加入跳躍風險後可使模型配適效果提升，尤其在模型中加入跳躍強度服從Hawkes Process的Merton Jump，其配適效果更勝於Merton Jump。整體而言，本研究發現，以S&P500指數為實證資料時，SVHJ模型有較好的配適效果。 / This paper, based on the Lévy process, considers two kinds of jump risk, Merton Jump and the Merton Jump whose jump intensity follows Hawkes Process. We use Particle Filter method and EM Algorithm to estimate the model parameters and calculate the log-likelihood value, AIC and BIC. We collect the S&P500 index for our empirical analysis and then compare the goodness of fit between the stochastic volatility model, the Variance Gamma model and two different jump risks. The empirical results show that the stochastic volatility model is better than the Variance Gamma model, and it is better to consider the jump risk in the model, especially the Merton Jump whose jump intensity follows Hawkes Process. The goodness of fit is better than Merton Jump. Overall, we find SVHJ model has better goodness of fit when S&P500 index was used as the empirical data.

在面臨2008年金融危機後嚴峻之需求面衝擊下，多國央行紛紛調降利率，甚至調降至零利率，以期望國家能盡速脫離經濟衰退。在利率調降的過程中，由於受零利率下限的限制，單純藉由傳統貨幣政策之調控，仍可能無法使經濟從嚴峻的需求面衝擊下恢復。因此，非傳統貨幣政策也在美國、日本、英國、歐元區等國家被央行所採行做為對抗經濟衰退的政策工具。在此背景下，我們想了解如何實施最適非傳統貨幣政策。 在最適貨幣政策理論發展中，最適傳統貨幣政策發展較早，因此也較為完備。而在最適非傳統貨幣政策方面，前瞻指引(forward guidance)這項政策工具已被引入最適理論中來進行討論，但量化寬鬆(quantitative easing)直至今日還未被引入最適理論中來討論。 因此，本文建構一個封閉的新興凱因斯模型(New Keynesian)，開創性的將量化寬鬆引入最適貨幣政策理論中，來討論最適傳統與非傳統貨幣政策，也藉此與過去文獻比較施行量化寬鬆與未施行量化寬鬆之影響。 / After financial crisis occurred in 2008, countries, such as United States of America, United Kingdom, Japan and the euro area, have been mired in slow economic growth, compared with long-term, and have confronted with severe negative demand shocks which can’t be offset by zero interest-rate policy. Under the circumstance where zero lower bound was present, unconventional monetary policy was implemented by central bank of each country to end up the economic recession prospectively. As a result, we are interested in how to implement optimal unconventional monetary policy. The literatures regarding implementing conventional optimal monetary policy under demand shock were developed maturely. Forward guidance, one of unconventional monetary policy, was already developed in field of optimal monetary policy under impacted by demand shock, but quantitative easing has not been conducted in the theory of optimal monetary policy so far. Thus, we construct a close-economy by New Keynesian model to conduct quantitative easing into the theory of optimal monetary policy to discuss the optimal conventional and unconventional monetary policy, and to compare the difference corresponding to the previous literatures which without quantitative easing.

本文的研究目的為，在一個含有房屋及房屋相關貸款的動態隨機一般均衡模型的架構中，比較貨幣政策、財政政策以及總體審慎政策對於房屋價格及房屋相關貸款的穩定效果。本文建構一個經濟封閉體系，其中包含三種不同家計單位、商品生產部門、房屋建商、資本生產部門，並且由政府部門制定相關政策；此模型的特色為，不同家計單位中的借貸行為、名目價格僵固性以及透過房屋價格抵押貸款的限制來刻劃金融摩擦。我們考慮了一般緊縮貨幣政策、提高財產稅率以及緊縮貸款價值比；本文發現，在三種政策中，對於抑制房屋價格以及降低住房貸款對國內生產毛額的比例，財政政策及總體審慎政策比起緊縮貨幣政策擁有較好的效果。 / The main purpose in this paper is to compare the effect of monetary policy, fiscal policy and macroprudential policy on housing price and housing related loans using a micro-based dynamic stochastic general equilibrium (DSGE) model with housing and housing related loans. We equip a closed economy model with three types of infinitely-lived households (patient households, impatient households and renters), a goods firm, housing and capital producer and a government sector. The model features borrowing and lending between patient and impatient households, nominal rigidity in goods price and financial friction in the form of collateral constraints tied to price of house. We consider the contractionary monetary policy by raising the interest rate, fiscal policy by increasing property tax rate and the macroprudential policy through tightening the loan-to-value (LTV) ratio. We find that among these three policies, in terms of dampening the price of housing and lowering the loan-to-GDP ratio, raising the property tax and lowering the LTV ratio outperforms the contractionary monetary policy.

本文旨在探討控制設計，而誤差項採用自我迴歸移動平均隨幾模式，損失函數分為平 方誤差與一般函數兩種。全文一冊，共分五章，約三萬餘子。內容如下： 第一章 導論：說明控制設計之目的，理想控制設計的條件，及本文的結構。 第二章 自我迴歸移動平均隨機模式：說明模式的理論基礎，性質，應用及模式的建 立。 第三章 動態系統隨機模式：說明模式的性質，建立，及應用。 第四章 控制設計：分為前饋控制、回饋控制，及一般損失函數的控制。 第五章 結論：說明本文所採用方法的利弊。

人口政策的制定需要人口推估作基礎。近年世界各國人口推估逐漸從專家意見推估走向機率推估，常見的機率推估分成三大類，隨機推估、模擬情境、推估誤差三種，本文所使用的人口推估方法為隨機推估法結合生育率之模擬情境方法，在人口變動要素組合法 (Cohort Component Method) 之下輔以電腦模擬的區塊拔靴法 (Block Bootstrap)，針對台灣地區與台灣北、中、南、東四地區進行人口推估。另外，本文試圖在隨機模型人口推估中加入遷移人口之考量，以期針對遷移人口在數量與其影響上都能有較深入的了解，比較區塊拔靴法與經建會推估之差異後發現遷移之考量確實會影響人口推估之結果。 / 針對與全區相符的小區域人口推估，本文亦提出可使得推估一致的方法，但其缺點為限制了生育、死亡人口要素之變動性。此推估在總數上與隨機推估方法差異不大，但在人口結構上則有明顯的差別，此差別可能是來自於死亡率在四區間差異造成。 / Population projection is important to policy making, and only with accurate population projection can the government achieve suitable policy planning and improve the welfare of the society. The most popular and well-known population projection method is the Cohort Component method, proposed since 1930’s. The trends of future fertility, mortality and migration are required, in order to apply the cohort component method. Currently in Taiwan, these trends are determined according to experts’ opinions (or scenario projection) and three future scenarios are assumed: high, median and low scenarios. One of the drawbacks in applying experts’ opinions is that the projection results of these three scenarios do not have the meaning in probability. / To modify the expert’ opinions and let the projection results carry the meaning in probability, many demographic researchers have developed stochastic projection methods. The proposed stochastic methods can be categorized into three groups: stochastic forecast, random scenario and ex post methods. In this study, we introduce these stochastic methods and evaluate the possibility of applying the methods in projecting the population in Taiwan. / In this study we use block bootstrap, a computer simulation and stochastic forecast method, to determine the trends of future fertility, mortality and migration in Taiwan, and combine it with the cohort component method for population projection in Taiwan. We compare the projection results with those from the Council for Economic Planning and Development (a scenario projection). We found that the block bootstrap is a possible alternative to the scenario projection in population projection, and the numbers of migration is small but have a non-ignorable influence on the future population. However, we also found that the block bootstrap alone might not be appropriate for population projection in small areas.

To date there is little evidence on the effect of property-liability (P-L) insurer's business strategy and organizational structure change on their frontier efficiency performance and productivity change. This issue is important since traditional theory assumes firms that minimizes cost and maximizes profit with more efficient strategy will survive in the long run. The main goal of this dissertation is to examine the efficiency performance in the U.S. P-L insurance industry using frontier efficiency and productivity methods. This dissertation consists of three essays on the efficiency studies. The first essay uses the data envelopment analysis to examine the efficiency performance and economies of scope for nonspecialists and specialists in the U.S. P-L insurance industry. The empirical evidence suggests that nonspecialists (specialists) dominate specialists (nonspecialists) in producing nonspecialists (specialists) input–output vectors and provide evidence for the coexistence of economies of scope and diseconomies of scope in the U.S. P-L insurance industry. Our second essay uses the stochastic frontier analysis to examine whether nonspecialized strategy dominates specialized strategy in the U.S. P-L insurance industry. The empirical evidence supports that both the nonspecialized hypothesis and the specialized hypothesis hold for different types of P-L insurers. Our third essay investigates whether the conversion of U.S. P-L insurers improves their efficiency performance before and after conversion. The empirical evidences of the value-added approach and the financial intermediary approach indicate that converting insurers experience improvement in their efficiency relative to mutual counter samples after the conversion, supporting the efficiency hypothesis proposed by Mayers and Smith (1986). Overall, the evidence of this dissertation shows that P-L insurer's diversification strategy and organizational structure change has significant impact on their frontier efficiency performance and productivity change.

本研究以確定給付型退休基金為對象，建構廣義隨機評價模型，以衡量不確定情況下退休基金之財務風險。希望藉著模型建構的過程，適切地描述基金評價過程中所應考量的各項要素。 為了強調基金評價時同時考量內外部精算假設的重要性，本研究將模型分為存活函數、經濟函數和給付函數三部份討論；存活函數利用離散時間非同質性半馬可夫過程（Discrete Time Non-Homogeneous semi-Markov Process）描述成員狀態轉移的機率，把成員工作年資、年齡和及狀態納入評價過程，有別於傳統僅以年齡為假設基礎之精算方法；經濟函數則以隨機過程表達外部環境的不確定性，結合上述假設資訊預估未來給付後，成為半馬可夫隨機精算評價模型，此一般性的模型能推展至基金評價時所需的各項流程。因此，本研究將模型應用於我國公務人員退撫基金，針對公務人員退撫基金的給付特性發展財務評價公式，完整地描述基金精算成本計算、未來人力與現金流量結構模擬以及敏感度分析等過程。 最後，本研究撰寫公務人員精算評價資訊系統，具體化半馬可夫隨機精算評價模型，實證公務人員退撫基金財務評價公式。實證結果也顯示，不論基金的性質或外部經濟環境，都將影響退休基金財務評價結果，為基金評價時不可忽略的精算假設。 / This study focuses on constructing a generalized valuation model for the defined benefit pension schemes. Financial soundness and funding stability are critical issues in pension fund management. In this study, a realistic stochastic model is built to monitor the uncertainty factors in affecting the financial risk and cash flow dynamics along the decision process. In order to evaluate the importance of the interior and exterior actuarial assumptions in pension valuation. Detailed models in describing the turnover patterns, economic uncertainties and benefit structures are explored. Semi-Markov process proposed by Dominicis, Manca and Granata (1991) and Janssen and Manca (1997) is extended in structuring the transition pattern of the plan’s population and the economic based factors are generated through stochastic processes. Modifications according to classification and movements of the plan member and the plan’s turnover pattern are employed to improve its practical usefulness. Then the actuarial valuations, cash flow analyses and workforce projection are performed and investigated. We has explicitly formulated the plan’s realistic phenomenon and implemented the proposed mechanism into a risk management framework for pension finance. By using this realistic approach, the cost factors could be monitored throughout the valuation. Typically these analyses involve substantial assumptions. This article has outlined the procedure of building the proposed model. Finally, Taiwan Public Employees Retirement System is simplified to illustrate the proposed methodology in pension valuation. The results from this study show that the structure of the pension schemes and the assumed economic factors are the significant factors in pension valuation. It also indicated that the fund manager can evaluate these impacts through the proposed model.