Mei Choi Chiu

• Doctor of Philosophy
• Professor (Associate) at Education University of Hong Kong

Empirical studies with publicly available life tables identify long-range dependence (LRD) in national mortality data. Although the longevity market is supposed to benchmark against the national force of mortality, insurers are more concerned about the forces of mortality associated with their own portfolios than the national ones. Recent advances...

This paper investigates the time-consistent mean-variance reinsurance-investment (RI) problem faced by life insurers. Inspired by recent findings that mortality rates exhibit long-range dependence (LRD), we examine the effect of LRD on RI strategies. We adopt the Volterra mortality model proposed in Wang et al. [(2021). Volterra mortality model: ac...

Continuous-time pairs trading rules are often developed based on the diffusion limit of the first-order vector autoregressive (VAR(1)) cointegration models. Empirical identification of cointegration effects is generally made according to discrete-time error correction representation of vector autoregressive (VAR(p)) processes, allowing for delayed...

This paper investigates the time-consistent mean-variance reinsurance-investment (RI) problem faced by life insurers. Inspired by recent findings that mortality rates exhibit long-range dependence (LRD), we examine the effect of LRD on RI strategies. We adopt the Volterra mortality model proposed in Wang et al.(2021) to incorporate LRD into the mor...

Any firm whose business strategy has an exposure constraint that limits its potential gain naturally considers expansion, as this can increase its exposure. We model business expansion as an enlargement of the opportunity set for business policies. However, expansion is irreversible and has an opportunity cost attached. We use the expected optimiza...

This paper investigates asset-liability management problems in a continuous-time economy. When the financial market consists of cointegrated risky assets, institutional investors attempt to make profit from the cointegration feature on the one hand, while on the other hand they need to maintain a stable surplus level, that is, the company’s wealth...

While abundant empirical studies support the long-range dependence (LRD) of mortality rates, the corresponding impact on mortality securities is largely unknown due to the lack of appropriate tractable models for valuation and risk management purposes. We propose a novel class of Volterra mortality models that incorporate LRD into the actuarial val...

Continuous-time pairs-trading rules are often developed based on the diffusion limit of first-order autoregressive cointegration models. Empirical identification of cointegration effects is generally made according to discrete-time error correction representation of vector autoregressive (VAR($p$)) processes. We show that the diffusion limit of a V...

This paper investigates asset-liability management problems in a continuous-time economy. When the financial market consists of cointegrated risky assets, institutional investors attempt to make profit from the cointegration feature on the one hand, while on the other hand they need to maintain a stable surplus level, that is, the company’s wealth...

While abundant empirical studies support the long-range dependence (LRD) of mortality rates, the corresponding impact on mortality securities are largely unknown due to the lack of appropriate tractable models for valuation and risk management purposes. We propose a novel class of Volterra mortality models that incorporate LRD into the actuarial va...

We propose a two-dimensional fast Fourier transform (FFT) network to retrieve the prices of options that depend on two Lévy processes. Applications include, but are not limited to, the valuation of options on two stocks under the Lévy processes, and options on a single stock under a random time-change Lévy process. The proposed numerical scheme can...

Subsistence consumption and investment problems with bankruptcy are classic constrained stochastic optimal control problem in financial economic, where the consumption rate should be greater than a positive number and the investor faces a bankruptcy payment. We derive novel asymptotic solution to this problem under the fast mean-reverting stochasti...

While cointegration models with constant parameters generate statistical arbitrage, the cointegration feature may change and even disappear due to regime shifts. This paper studies the time-consistent mean-variance portfolio problem in a Markov-modulated regime-switching cointegration economy. We derive a novel closed-form solution to the equilibri...

Levy and Levy (2009) empirically show that a combination of safety first and expected utility (SFEU) principles play a key role in human decision-making process. This paper extends the SFEU model to the optimal dynamic investment in a continuous-time economy. We derive the analytic optimal trading strategy using the martingale approach. Interesting...

This article investigates the optimal investment for insurers with correlation risk, with the variance– covariance matrix among risky financial assets evolving as a stochastic positive definite matrix process. Using the Wishart diffusion matrix process, we formulate the insurer’s investment problem as the max- imization of the expected constant rel...

This paper investigates the robust optimal pairs trading using the concept of equivalent probability measures and a penalty function associated with the confidence in parameter estimates when the parameters in the drift term of the continuous-time cointegration model are estimated with errors. A closed-form solution is derived for the robust pairs...

The sub-prime mortgage crisis of 2008 had a great effect on the financial market; it led to new market features and regulations. In particular, the dual curve feature has appeared in the over-the-counter market. As a result, the yield curve for computing forward values and the yield curve for discounting are no longer the same due to counterparty d...

This paper extends the fast Fourier transform (FFT) network to interest derivative valuation under the Hull–White model driven by a Lévy process. The classical trinomial tree for the Hull–White model is a widely adopted approach in practice, but fails to accommodate the change in the driving stochastic process. Recent finance research supports the...

Using the technique of dynamic portfolio optimization, Chiu and Li (Insur. Math. Econ. 39:330–355, 2006) pioneered the optimal asset-liability management (ALM) framework for investors and insurers in a continuous-time economy. Their approach has been generalized to different objective functions under different stochastic models for the assets and t...

Investors interested in the global financial market must analyze financial securities internationally. Making an optimal global investment decision involves processing a huge amount of data for a high-dimensional portfolio. This article investigates the big data challenges of two mean-variance optimal portfolios: continuous-time precommitment and c...

This paper investigates the impact of relative performance concerns on the longevity risk transfer market. When an insurer concerns about the relative performance in a two-insurer economy, she maximizes the expected utility of her terminal wealth benchmarked against her competitor’s. The problem formulation for a general utility, a general interest...

Cointegration is a useful econometric tool for identifying assets which share a common equilibrium. Cointegrated pairs trading is a trading strategy which attempts to take a profit when cointegrated assets depart from their equilibrium. This paper investigates the optimal dynamic trading of cointe-grated assets using the classical mean-variance por...

This article investigates the dynamic mean-variance hedging problem of an insurer using longevity bonds (or longevity swaps). Insurance liabilities are modeled using a doubly stochastic compound Poisson process in which the mortality rate is correlated and cointegrated with the index mortality rate. We solve this dynamic hedging problem using a the...

Empirically, cointegration and stochastic covariances, including stochastic volatilities, are statistically significant for commodity prices and energy products. To capture such market phenomena, we develop a continuous-time dynamics of cointegrated assets with a stochastic covariance matrix and derive the joint characteristic function of asset ret...

Consider an insurer who invests in the financial market where correlations among risky asset returns are randomly changing over time. The insurer who faces the risk of paying stochastic insurance claims needs to manage her asset and liability by taking into account of the correlation risk. This paper investigates the impact of correlation risk to t...

A fundamental challenge for insurance companies (insurers) is to strike the best balance between optimal investment and risk management of paying insurance liabilities, especially in a low interest rate environment. The stochastic interest rate becomes a critical factor in this asset-liability management (ALM) problem. This paper derives the closed...

The Markowitz mean–variance portfolio selection (MVPS) problem is the building block of modern portfolio theory. Since Markowitz (1952) published his seminal study, there have been numerous extensions to the continuous-time MVPS problem under different market conditions. This paper further enriches the literature by taking account of correlation ri...

This paper investigates the time-consistent dynamic mean–variance hedging of longevity risk with a longevity security contingent on a mortality index or the national mortality. Using an HJB framework, we solve the hedging problem in which insurance liabilities follow a doubly stochastic Poisson process with an intensity rate that is correlated and...

Using the diffusion limit of the discrete-time error correction model of cointegration for risky assets and geometric Brownian motion for the value of liabilities, we solve the asset-liability management (ALM) problem using the theory of backward stochastic differential equations. The solutions of the ALM policy and the efficient frontier in terms...

This paper considers the optimal investment problem for an insurer that invests in cointegrated assets subject to the random payments of insurance claims. The insurer’s objective is to maximize the expected utility of the terminal wealth subject to the cointegration dynamics of risky assets and the risk of paying out random liabilities with a compo...

Turbo warrants are liquidly traded financial derivative securities in over-the-counter and exchange markets in Asia and Europe. The structure of turbo warrants is similar to barrier options, but a lookback rebate will be paid if the barrier is crossed by the underlying asset price. Therefore, the turbo warrant price satisfies a partial differential...

The cointegration of major financial markets around the globe is well evidenced with strong empirical support. This paper considers the continuous-time mean–variance (MV) asset–liability management (ALM) problem for an insurer investing in an incomplete financial market with cointegrated assets. The number of trading assets is allowed to be less th...

Roy pioneers the concept and practice of risk management of disastrous events via his safety-first principle for portfolio selection. More specifically, his safety-first principle advocates an optimal portfolio strategy generated from minimizing the disaster probability, while subject to the budget constraint and the mean constraint that the expect...

Cointegration and stochastic correlations, including stochastic volatilities, are statistically significant for the spot prices of crude oil and gasoline. As these commodities are not traded on exchange, their futures prices provide us with strong empirical support that cointegration contributes significantly to the stochastic movements of their co...

This paper considers the continuous-time mean-variance portfolio selection problem in a financial market in which asset prices are cointegrated. The asset price dynamics are then postulated as the diffusion limit of the corresponding discrete-time error-correction model of cointegrated time series. The problem is completely solved in the sense that...

This work investigates the valuation of options when the underlying asset follows a mean-reverting log-normal process with a stochastic volatility that is driven by two stochastic processes with one persistent factor and one fast mean-reverting factor. Semi-analytical pricing formulas for European options are derived by means of multiscale asymptot...

This paper investigates option pricing on two co-integrated assets with each asset having multivariate stochastic volatility. We consider the diffusion limit of error correction model of co-integrated time series with stochastic volatility and then derive closed-form solution to the joint characteristic function of the two assets. This allows us to...

Under the safety-first principle (Roy in Econometrica 20:431–449, 1952), one investment goal in asset-liability (AL) management is to minimize an upper bound of the ruin probability which measures the likelihood of the final surplus being less than a given target level. We derive solutions to the safety-first AL management problem under both contin...

A matrix called Varchenko matrix associated with a hyperplane arrangement was defined by A. N. Varchenko in 1991. Matrices that we shall call q-matrices are induced from Varchenko matrices. Many researchers are interested the invariant factors of these q-matrices. Shiu put this problem to the graph model. In this paper, invariant factors of Cartesi...

Asset and liability (AL) management under the mean–variance criteria refers to an optimization problem that maximizes the expected final surplus subject to a given variance of the final surplus or, equivalently, minimizes the variance of the final surplus subject to a given expected final surplus. We employ stochastic optimal control theory to anal...