none

The purpose of this thesis aims that common investors are expected to apply three kinds of active portfolio management without complex mathematical numeration to reduce investment risk or loss to get profits on Taiwan stock exchange capitalization weighted stock index options market. They are Constant Portion Portfolio Insurance Strategy (named CPPI), Time-Invariant Portfolio Protection (named TIPP) and Constant Mix Strategy (named CMS). The active managements adopt bull and bear spread as an adjustment of risk positions on the option market. Five research results are as followings: 1. The performance of the portfolio managements as Constant Portion Portfolio Insurance Strategy and Time - Invariant Portfolio Protection is better than that of the management as Constant Mix Strategy. And Floor value of the portfolio management as Time - Invariant Portfolio Protection exceeds that of the portfolio management as Constant Portion Portfolio Insurance Strategy. 2. Due to the regulation of margin system by Taiwan Future Exchange, the positions of Bull Call Spread and Bear Put Spread can be greater than ones of Bull Put Spread and Bear Call Spread. 3. The more differences between two strike prices on the spread option means to be able to get more profit opportunities. 4. Greater multiplier number and profit have inverse relationship. That only occurs on portfolio managements in Constant Portion Portfolio Insurance Strategy and Time - Invariant Portfolio Protection. 5. Setting upper and low limitation of single return rate for offsetting will have better performance than no limitations for the managements in Constant Portion Portfolio Insurance Strategy and Time - Invariant Portfolio Protection.

Cette thèse a pour objectif d’évaluer et de comparer la performance des stratégies d’assurance de portefeuille pour tenter de définir quelles stratégies doivent être privilégiées par les investisseurs. Nous comparons de nombreuses stratégies d’assurance (OBPI, CPPI, put synthétique et Stop-loss) entre elles mais également avec quelques autres stratégies de référence. Nous utilisons différents critères de comparaison qui comprennent: 1. Les distributions de pay-off, le niveau de protection, la dominance stochastique et le coût d’assurance dans différentes conditions de marché identifiées par des modèles à changements de régime markovien. 2. Les mesures de la performance ajustée au risque qui peuvent refléter les préférences des investisseurs vis-à-vis du risque et de la rentabilité. 3. Les préférences des investisseurs en intégrant la théorie cumulative des perspectives (TCP). Nos résultats semblent mettre en évidence une dominance des stratégies CPPI dans la majorité des cas et pour la majorité des critères de comparaison. / This thesis is set out with the objective of evaluating and comparing the performance of portfolio insurance strategies. We try to figure out when and why one portfolio insurance strategy should be preferred by investors in practice. To meet this objective, main portfolio insurance strategies (OBPI, CPPI, Synthetic put and Stop-loss) are compared relatively to each other and to some benchmark strategies. Portfolio insurance strategies are applied within different implementation scenarios and compared according to various criteria that include:1. The payoff functions, stochastic dominance, the level of protection and the cost of insurance under bull and bear market conditions. 2. Various risk adjusted performance measures that reflect different investors’ preferences toward risk and return. 3. The preferences of investors who act according to cumulative prospect theory (CPT). Our results reveal a dominant role of CPPI strategy at the majority of cases and according to the majority of comparison criteria.

2008年金融海嘯、2011歐債危機等，皆對台灣經濟產生嚴重的損失。壽險業經營關乎保戶之未來，應更加重視壽險業經營穩健性，故本研究期望找尋適當的保本投資策略，期望增加壽險業的投資選擇，提供穩定且合理的獲利。 引用Cai et al. (2013)之保護下檔風險之最適投資策略模型，將資產配置視為無風險性資產與購買一個歐式買權，此歐式買權可藉由市場可交易之標的複製，最低績效標準為執行價(Strike Price)、距離到期日天數為買權到期日(Expiry Date)。本研究亦(1)比較不同利率市場下，保護下檔風險之最適投資策略、CPPI與TIPP之投資績效與保本效果；與(2)不同下檔風險容忍度、(3)不同風險權益市場下，經理人之投資決策與投資績效。 本研究發現(1)保護下檔風險之最適投資策略於高利率市場與一般利率市場下，彈性最高且整體獲利高、波動小；而TIPP因投資策略相當保守，於低利率市場下獲利及保本效果為三者最好。(2)當委託人改變契約，下檔風險容忍度降低時，經理人增加股票型基金部位，並拉長投資期間以提高績效。適當降低下檔風險容忍度，有助於使風險趨避經理人追逐風險。(3)面對環境快速變遷，探討不同風險權益市場對經理人績效之影響，發現於高風險權益資本市場下，面對績效壓力，將採用放空債券與增加股票部位並行的投資策略，造成財富波動大且績效降低。於低權益市場則是債券為主要標的，投資績效較為穩定。委託人可視不同狀況及早訂定委託契約，降低財富波動。

Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-11-09T18:21:24Z No. of bitstreams: 1 JoseHenriquedeOliveiraVarandaDissertacao2018.pdf: 3107527 bytes, checksum: ea06abcabf1c014758cc880bcf0b0726 (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-11-13T16:00:57Z (GMT) No. of bitstreams: 1 JoseHenriquedeOliveiraVarandaDissertacao2018.pdf: 3107527 bytes, checksum: ea06abcabf1c014758cc880bcf0b0726 (MD5) / Made available in DSpace on 2018-11-13T16:00:57Z (GMT). No. of bitstreams: 1 JoseHenriquedeOliveiraVarandaDissertacao2018.pdf: 3107527 bytes, checksum: ea06abcabf1c014758cc880bcf0b0726 (MD5) Previous issue date: 2018-07-02 / This study evaluates which modifications can restore the theoretical performance of dynamic asset allocation strategies that uses insurance and leverage, specifically those known as Constant Proportion Portfolio Insurance (CPPI), when confronted with realistic premises and scenarios. Simulations using GARCH models are applied to assess the effects of path dependency and volatility on those strategies and to evaluate how selected modifications mitigates those effects. These modifications are tested using the Farinelli- Tibilleti ratio and derivations, like de Upside Potential Ratio. As main finding, the modifications that mitigates path dependency can restore the theoretical performance of portfolio insurance with high significance, making those preferred strategies in relation to Buy-and-Hold (BH) or Constant-Mix (CM) for most investors in several scenarios. This work also presents a novel modification, adapted for the risk-free market in Brazil, that resulted in the best performing portfolio insurance strategy with great significance. / Este trabalho avalia quais modificações reestabelecem o desempenho teórico das estratégias dinâmicas de alocação de ativos com seguro e alavancagem, denominadas Constant Proportion Portfolio Insurance (CPPI), quando confrontadas com premissas e cenários realistas. São realizadas simulações de modelos da família GARCH, com parâmetros estimados do mercado, para exercitar os efeitos da dependência do caminho e da volatilidade nestas estratégias e avaliar como as modificações selecionadas ajudam a combate-los. A significância das modificações é testada pela medida Farinelli-Tibiletti, sobre tudo a combinação que resulta na razão Upside Potential, onde conclui-se que existem modificações significantes que são capazes de resgatar o desempenho teórico da estratégia CPPI, inclusive tornando-a preferível às estratégias clássicas Buy-and-Hold (BH) e Constant-Mix (CM) em certos cenários. Por fim, o trabalho apresenta uma modificação inovadora, derivada do ajuste à realidade do mercado brasileiro, que acabou por apresentar o maior nível de desempenho relativo do método CPPI, com elevada significância.

The selection of investment strategies and managing investment funds via employing portfolio insurance methods play an important role in asset liability management. Insurance strategies are designed to limit downside risk of portfolio while allowing some participation in potential gain of upside markets. In this thesis, we provide an extensive overview and investigation, particularly on the two most prominent portfolio insurance strategies: the Constant Proportion Portfolio Insurance (CPPI) and the Option-Based Portfolio Insurance (OBPI). The aim of the thesis is to examine, analyze and compare the portfolio insurance strategies in terms of their performances at maturity, via some of their statistical and dynamical properties, and of their optimality over the maximization of expected utility criterion. This thesis presents the financial market model in continuous-time containing no arbitrage opportunies, the CPPI and OBPI strategies with definitions and properties, and the analysis of these strategies in terms of comparing their performances at maturity, of their statistical properties and of their dynamical behaviour and sensitivities to the key parameters during the investment period as well as at the terminal date, with both formulations and simulations. Therefore, we investigate and compare optimal portfolio strategies which maximize the expected utility criterion. As a contribution on the optimality results existing in the literature, an extended study is provided by proving the existence and uniqueness of the appropriate number of shares invested in the unconstrained allocation in a wider interval.

A robust computational framework is presented for the risk-neutral valuation of capital guarantees written on discretely-reallocated portfolios following the Constant Proportion Portfolio Insurance (CPPI) strategy. Aiming to address the (arguably more realistic) cases where analytical results are unavailable, this framework accommodates risky-asset jumps, volatility surfaces, borrowing restrictions, nonuniform reallocation schedules and autonomous CPPI floor trajectories. The two-asset state space representation developed herein facilitates visualising the CPPI strategy, which in turn provides insight into grid design and interpolation. It is demonstrated that given a deterministic process for the risk-free rate, the pricing problem can be cast as solving cascading systems of 1D partial integro-differential equations (PIDEs). This formulation’s stability and monotonicity are studied. In addition to making more sense financially, the limited borrowing variant of the CPPI strategy is found to be better suited than the classical (unlimited borrowing) counterpart for bounded-domain calculations. Consequently, it is demonstrated how the unlimited borrowing problem can be approximated by imposing an artificial borrowing limit. For implementation validation, analytical solutions to special cases are derived. Numerical tests are presented to demonstrate the versatility of this framework.

A robust computational framework is presented for the risk-neutral valuation of capital guarantees written on discretely-reallocated portfolios following the Constant Proportion Portfolio Insurance (CPPI) strategy. Aiming to address the (arguably more realistic) cases where analytical results are unavailable, this framework accommodates risky-asset jumps, volatility surfaces, borrowing restrictions, nonuniform reallocation schedules and autonomous CPPI floor trajectories. The two-asset state space representation developed herein facilitates visualising the CPPI strategy, which in turn provides insight into grid design and interpolation. It is demonstrated that given a deterministic process for the risk-free rate, the pricing problem can be cast as solving cascading systems of 1D partial integro-differential equations (PIDEs). This formulation’s stability and monotonicity are studied. In addition to making more sense financially, the limited borrowing variant of the CPPI strategy is found to be better suited than the classical (unlimited borrowing) counterpart for bounded-domain calculations. Consequently, it is demonstrated how the unlimited borrowing problem can be approximated by imposing an artificial borrowing limit. For implementation validation, analytical solutions to special cases are derived. Numerical tests are presented to demonstrate the versatility of this framework.

由於固定比例投資組合保險策略(CPPI)能依據投資者本身的風險偏好來選定參數，並透過簡單的公式動態調整風險性資產及保留性資產的部位，以達到投資組合保險的目的，因此成為常用的投資組合保險策略之一。然而在固定乘數的選定中，僅考慮投資人的效用函數而並未考慮市場變化情況，因此投資組合的報酬往往未必為最適化之結果。 　　本研究以台灣股市為例，旨在討論透過技術分析指標來動態調整乘數，對固定比例投資組合保險策略之影響。實證方面以1992~2003年間台股指數作為研究標的，配合固定時點調整法及相對強弱指標來調整投資組合中風險性資產及保留性資產之投資比例。並討論動態調整與固定乘數在要保誤差、平均報酬、報酬變異、偏態、交易成本及不同市況下績效表現。

投資組合保險的概念發源自1980年代，對於較保守或是對於股市未來走勢不清楚的投資人來說，是一種不錯的投資策略，既可以保障原本所投資的本金，亦可參與上方的獲利。投資組合保險策略所運用的範疇很廣，尤其適用於大筆資金之持有者，且只願意承受一定範圍的損失風險，如：退撫基金、保險基金或各類信託基金之基金經理人。 本研究以台灣50ETF(指數股票型基金)為研究對象，探討複製性賣權及固定比例投資組合保險等兩種資產配置策略，在不同市況下(2006年至2011年)之績效，並與買入持有策略做比較。其中，本文以GARCH波動度模型估計複製性賣權策略中之波動度；在CPPI策略中，由於考量到不同市場狀況下，投資人之風險偏好程度應會有所不同，風險乘數亦會有所改變，因此本文將風險乘數最適化，以改善傳統之固定風險乘數CPPI策略。 由本研究之實證結果可以得到以下結論： 1. 複製性賣權策略在空頭市場之績效會比買入持有策略及台灣50ETF好。然而，在大空頭時，由於股價急速下滑，導致資產配置來不及調整，而產生保險誤差。另外，複製性賣權在多頭市況下，較低的保本比例，會帶來較高之報酬。 2. CPPI策略在各種市況下，其績效大致都會優於買入持有策略，且完全沒有出現保險誤差，但只有在空頭走勢下，CPPI會打敗市場，原因在於CPPI發揮了保護下檔風險的功能，且說明了投資組合保險策略之目的並非超越市場報酬。 3. 將複製性賣權策略與CPPI策略相比時，從報酬率來看，空頭市場下CPPI的保護功能較複製性賣權強，而多頭或盤整市況下，並無一致的結果。從Sharpe ratio、長期相對平均成本、上方獲取率損失等績效指標，CPPI大致上都比複製性賣權好得多。