Dynamic Prudential Regulation: Is Prompt Corrective Action Optimal?

The current U.S. bank capital regulation features prompt corrective action, which mandates regulators to intervene in and liquidate banks based on their book‐value capital ratios. To see if prompt corrective action is optimal, I build a dynamic model of repeated interactions between a banker and a regulator. Under hidden choice of risk, private information on returns and limited commitment by the banker, and costly liquidation, I first characterize the optimal incentive‐feasible allocation. I then demonstrate that the optimal allocation is implementable through the combination of a risk‐based deposit insurance premium and a book‐value capital regulation with stochastic liquidation.     

基于Copula函数的保险公司经济资本配置研究

经济资本的度量及配置是风险管理的核心内容。本文利用Copula函数构建保险公司总体风险的联合分布函数,结合TCE方法来度量保险公司经济资本,并利用动态规划方法对经济资本最优配置模型求解。最后结合中国人民财产保险股份有限公司的数据进行实证。通过研究发现,我国财险公司内部偿付能力状况较好,但险种结构有待优化。     

Mitigating Estimation Risk in Asset Allocation: Diagonal Models Versus 1/N Diversification

Recent literature suggests that optimal asset‐allocation models struggle to consistently outperform the 1/N naïve diversification strategy, which highlights estimation‐risk concerns. We propose a dichotomous classification of asset‐allocation models based on which elements of the inverse covariance matrix that a model uses: diagonal only versus full matrix. We argue that parsimonious diagonal‐only strategies, which use limited information such as volatility or idiosyncratic volatility, are likely to offer a good tradeoff between incorporating limited information while mitigating estimation risk. Evaluating five sets of portfolios over 1926–2012, we find that 1/N is generally not optimal when compared with these diagonal strategies.     

Risk management strategies for banks

We analyze optimal risk management strategies of a bank financed with deposits and equity in a one period model. The bank’s motivation for risk management comes from deposits which can lead to bank runs. In the event of such a run, liquidation costs arise. The hedging strategy that maximizes the value of equity is derived. We identify conditions under which well known results such as complete hedging, maximal speculation or irrelevance of the hedging decision are obtained. The initial debt ratio, the size of the liquidation costs, regulatory restrictions, the volatility of the risky asset and the spread between the riskless interest rate and the deposit rate are shown to be the important parameters that drive the bank’s hedging decision. We further extend this basic model to include counterparty risk constraints on the forward contract used for hedging.     

To Hedge or Not to Hedge: Managing Demographic Risk in Life Insurance Companies

Demographic risk, i.e., the risk that life tables change in a nondeterministic way, is a serious threat to the financial stability of an insurance company having underwritten life insurance and annuity business. The inverse influence of changes in mortality laws on the market value of life insurance and annuity liabilities creates natural hedging opportunities. Within a realistically calibrated shareholder value (SHV) maximization framework, we analyze the implications of demographic risk on the optimal risk management mix (equity capital, asset allocation, and product policy) for a limited liability insurance company operating in a market with insolvency‐averse insurance buyers. Our results show that the utilization of natural hedging is optimal only if equity is scarce. Otherwise, hedging can even destroy SHV. A sensitivity analysis shows that a misspecification of demographic risk has severe consequences for both the insurer and the insured. This result highlights the importance of further research in the field of demographic risk.     

Capital Market Development,Competition, Property Rights,and the Value of Insurer Product‐Line Diversification: A Cross‐Country Analysis

In this article, we show that the effect of product diversification on performance is not homogeneous across countries. Diversified insurance companies perform significantly worse than their focused competitors in countries with well‐developed capital markets, high levels of property rights protection, and high levels of competition. In addition, we find that the diversification–performance relationship for insurance companies depends on company size. For large insurers operating in countries with less developed capital markets, diversification significantly increases performance. Our results suggest that the optimal organizational structure may be different for insurers operating in emerging economies than for insurers operating in developed countries.     

Optimal Reinsurance Arrangements Under Tail Risk Measures

Regulatory authorities demand insurance companies control their risk exposure by imposing stringent risk management policies. This article investigates the optimal risk management strategy of an insurance company subject to regulatory constraints. We provide optimal reinsurance contracts under different tail risk measures and analyze the impact of regulators' requirements on risk sharing in the reinsurance market. Our results underpin adverse incentives for the insurer when compulsory Value-at-Risk risk management requirements are imposed. But economic effects may vary when regulatory constraints involve other risk measures. Finally, we compare the obtained optimal designs to existing reinsurance contracts and alternative risk transfer mechanisms on the capital market.     

TACTICAL ASSET ALLOCATION: CAN IT WORK?

Market events of the past ten years have sparked an interest in tactical asset allocation. In the current study we develop and test a model that incorporates currently available information into the tactical asset allocation process. The model provides an estimate of the probabilities that the upcoming market period will be bullish or bearish. Logit analysis is employed to determine which of the various timely and readily available data significantly affect these probabilities. These estimated probabilities are used to suggest the optimal allocations of funds over time between the risk-free asset and the market portfolio. Then, several timing strategies are compared with a buy-and-hold portfolio. An asset allocation strategy based on the probabilities assigned by the logit model appears to achieve greater terminal wealth with less variability of returns. Similar results are obtained for both an initial sample (1962–76 in our model) and a holdout sample (1977–88).     

Asset tangibility and capital allocation

Firms comprise divisions that often differ with respect to the degree of asset tangibility. As the strength of borrowing constraints depends on the liquidation value of assets, these firms influence their debt capacity by allocating funds across divisions. We argue that a company whose capital allocation is not verifiable suffers from a dynamic inconsistency problem, as it tends to allocate resources in favor of divisions with fewer tangible assets, leading to a tight borrowing constraint. When capital allocation is verifiable, committing to invest only little there eases this constraint, although it implies a deviation from a return maximizing allocation.     

Portfolio Optimization under Solvency Constraints: A Dynamical Approach

We develop portfolio optimization problems for a nonlife insurance company seeking to find the minimum capital required that simultaneously satisfies solvency and portfolio performance constraints. Motivated by standard insurance regulations, we consider solvency capital requirements based on three criteria: ruin probability, conditional Value-at-Risk, and expected policyholder deficit ratio. We propose a novel semiparametric formulation for each problem and explore the advantages of implementing this methodology over other potential approaches. When liabilities follow a Lognormal distribution, we provide sufficient conditions for convexity for each problem. Using different expected return on capital target levels, we construct efficient frontiers when portfolio assets are modeled with a special class of multivariate GARCH models. We find that the correlation between asset returns plays an important role in the behavior of the optimal capital required and the portfolio structure. The stability and out-of-sample performance of our optimal solutions are empirically tested with respect to both the solvency requirement and portfolio performance, through a double rolling window estimation exercise.     

Does one size fit all? Determinants of insurer capital structure around the globe

As financial markets become more global, the question arises whether any country specific considerations are still relevant for insurance companies’ capital structure. This research examines this question with firm-level data across a broad range of countries including those in developing markets. What we find is that the optimal capital structure of insurance companies is not homogeneous across countries. We find that country-level factors explain a substantial fraction of the cross-sectional variation in insurance companies’ capitalization levels. Our results add to the current policy discussion on global regulatory capital requirements. If insurer capital structure is not homogeneous across countries, a global capital standard – if desired – should take differences in the institutional environments across countries into account to avoid market distortions.     

Incentives and financial crises: Microfounded macroprudential regulation

We provide a micro-based rationale for macroprudential capital regulation of financial intermediaries (banks) by developing a model in which bankers can privately undertake a costly effort and reduce the probability of adverse shocks to their asset holdings that force liquidation (deterioration risk). A decline in the fundamental risk of assets ameliorates funding conditions, boosting the banks’ ability to expand their balance sheets. In principle, a higher continuation value would improve incentives to put effort. However, the rise in asset demand and prices also increases the payoff in liquidation, eventually reducing the equilibrium optimal effort. Poor incentives impose socially inefficient liquidation and can be corrected through a regulatory capital requirement. We show that the requirement should be high when fundamental risk is low. Therefore, the model suggests a theoretical foundation for macroprudential regulation and the countercyclical capital buffer of Basel III.     

An Optimal Product Mix for Hedging Longevity Risk in Life Insurance Companies: The Immunization Theory Approach

This article investigates the natural hedging strategy to deal with longevity risks for life insurance companies. We propose an immunization model that incorporates a stochastic mortality dynamic to calculate the optimal life insurance–annuity product mix ratio to hedge against longevity risks. We model the dynamic of the changes in future mortality using the well‐known Lee–Carter model and discuss the model risk issue by comparing the results between the Lee–Carter and Cairns–Blake–Dowd models. On the basis of the mortality experience and insurance products in the United States, we demonstrate that the proposed model can lead to an optimal product mix and effectively reduce longevity risks for life insurance companies.     

Capital Allocation for Insurance Companies—What Good IS IT?

In their 2001 Journal of Risk and Insurance article, Stewart C. Myers and James A. Read Jr. propose to use a specific capital allocation method for pricing insurance contracts. We show that in their model framework no capital allocation to lines of business is needed for pricing insurance contracts. In the case of having to cover frictional costs, the suggested allocation method may even lead to inappropriate insurance prices. Beside the purpose of pricing insurance contracts, capital allocation methods proposed in the literature and used in insurance practice are typically intended to help derive capital budgeting decisions in insurance companies, such as expanding or contracting lines of business. We also show that net present value analyses provide better capital budgeting decisions than capital allocation in general.     

Optimal Gradual Annuitization: Quantifying the Costs of Switching to Annuities

We compute the optimal dynamic annuitization and asset allocation policy for a retiree with Epstein–Zin preferences, uncertain investment horizon, potential bequest motives, and pre‐existing pension income. In our setting the retiree can decide each year how much he consumes and how much he invests in stocks, bonds, and life annuities, while the prior literature mostly considered restricted so‐called deterministic or stochastic switching strategies. We show that postponing the annuity purchase is no longer optimal in the gradual annuitization (GA) case since investors are able to attain the optimal mix between liquid assets (stocks and bonds) and illiquid life annuities each year. In order to assess potential utility losses, we benchmark various restricted annuitization strategies against the unrestricted GA strategy.     

Dynamic preferences for popular investment strategies in pension funds

In this paper, we characterize dynamic investment strategies that are consistent with the expected utility setting and more generally with the forward utility setting. Two popular dynamic strategies in the pension funds industry are used to illustrate our results: a constant proportion portfolio insurance (CPPI) strategy and a life-cycle strategy. For the CPPI strategy, we are able to infer preferences of the pension fund’s manager from her investment strategy, and to exhibit the specific expected utility maximization that makes this strategy optimal at any given time horizon. In the Black–Scholes market with deterministic parameters, we are able to show that traditional life-cycle funds are not optimal to any expected utility maximizers. We also prove that a CPPI strategy is optimal for a fund manager with HARA utility function, while an investor with a SAHARA utility function will choose a time-decreasing allocation to risky assets in the same spirit as the life-cycle funds strategy. Finally, we suggest how to modify these strategies if the financial market follows a more general diffusion process than in the Black–Scholes market.     

DETERMINANTS OF CAPITAL STRUCTURE IN BUSINESS START‐UPS: THE ROLE OF NONFINANCIAL STAKEHOLDER RELATIONSHIP COSTS

According to the finance literature, nonfinancial stakeholders (NFS), such as customers, suppliers, and employees, take into account their expected liquidation costs when dealing with a firm. In this framework, firms can influence their probability of liquidation by choosing an appropriate capital structure. Also, the literature suggests NFS bargaining power may affect firm financing decisions. In the current article we investigate these ideas for initial financing decisions by business start‐ups, where ex ante failure risk is high and NFS must decide whether to make relationship‐specific investments. We find that start‐ups imposing larger costs on their NFS following liquidation significantly reduce leverage. This effect is strengthened when suppliers have greater bargaining power. We also document a marginally negative effect of NFS liquidation costs on the proportion of bank loans. Finally, business start‐ups rely less on bank loans when customers and suppliers are in a powerful bargaining position.     

Optimal holding period for assets that must be liquidated: A certainty equivalent wealth approach

Consumers often invest with a specific goal in mind and often know with some precision when the investment proceeds will be needed to achieve that goal. Because different investors have different attitudes toward risk and because different asset types exhibit different risk characteristics, there is often confusion as to the appropriate investment asset for a particular investor with a known investment horizon. It is also frequently, unclear as to whether investments should be switched to a less risky asset as time to liquidation becomes short. This paper addresses the issues of initial asset choice and the advisability of switching among assets when the investment goal date is known, employing the methodology of certainty equivalent wealth. In addition to suggesting optimal investment strategies for individuals based upon holding period and degree of risk aversion, it shows that switching investment assets produces suboptimal results.     

Der Einsatz interner Modelle beim mehrj?hrigen Enterprise Risk Management

Increasing natural catastrophes, recent dynamics in capital markets, and fundamental changes in regulatory requirements (e.g., Solvency II for European Union member countries) have placed increasing challenges in management of insurance companies. While in the Solvency II framework the time horizon is one year, the strategic risk-return profile of the insurer should be set according to multi-year calculations. The aim of this paper is to introduce a multi-year risk-capital concept. This multi-year approach can help management to answer the following essential question: ??How many future years with extreme catastrophes or adverse capital market developments can the company withstand at a certain confidence level without external capital supply??? In the context of multi-year enterprise risk management a capital allocation method is needed in order (1) to set risk limitations for different segments, for example different lines of business and different years, and (2) to quantify the effect of management strategies on risk-adjusted performance indicators, defined per segment. We define a capital allocation method in the multi-year context and illustrate the use of the multi-year risk-capital concept within a simulation study.     

Analysis of Participating Life Insurance Contracts: A Unification Approach

Fair pricing of embedded options in life insurance contracts is usually conducted by using risk‐neutral valuation. This pricing framework assumes a perfect hedging strategy, which insurance companies can hardly pursue in practice. In this article, we extend the risk‐neutral valuation concept with a risk measurement approach. We accomplish this by first calibrating contract parameters that lead to the same market value using risk‐neutral valuation. We then measure the resulting risk assuming that insurers do not follow perfect hedging strategies. As the relevant risk measure, we use lower partial moments, comparing shortfall probability, expected shortfall, and downside variance. We show that even when contracts have the same market value, the insurance company's risk can vary widely, a finding that allows us to identify key risk drivers for participating life insurance contracts.