Dynamic Portfolio Choice with Stochastic Wage and Life Insurance

We study optimal insurance, consumption, and portfolio choice in a framework where a family purchases life insurance to protect the loss of the wage earner's human capital. Explicit solutions are obtained by employing constant absolute risk aversion utility functions. We show that the optimal life insurance purchase is not a monotonic function of the correlation between the wage and the financial market. Meanwhile, the life insurance decision is explicitly affected by the family's risk preferences in general. The model also predicts that a family uses life insurance and investment portfolio choice to hedge stochastic wage risk.     

Portfolio choice and mortality-contingent claims: The general HARA case

We solve a portfolio choice problem that includes mortality-contingent claims and labor income under general HARA preferences. Our contribution beyond existing literature is to (i) focus on the covariance between shocks to human capital and financial capital, to (ii) model the utility of a family with basic needs and (iii) include life insurance and pension annuity claims in one unified life-cycle model. Our solution employs a “similarity reduction” mapping which reduces the two-dimensional HJB equation into one dimension. This allows for the implementation of a quick numerical scheme. And, when shocks to human capital and financial capital are perfectly correlated, a closed-form expression is obtained as a special case.     

Global financial shocks and foreign asset repatriation: Do local investors play a stabilizing role?

We study the dynamic response of gross capital flows in emerging market economies to different global financial shocks, using a panel vector-autoregressive (PVAR) approach. Our focus lies primarily on the potentially stabilizing role played by domestic investors in offsetting the response of foreign investors to adverse global shocks. We find that, while foreign investors tend to retrench from emerging markets in response to global risk aversion and monetary policy shocks, foreign asset repatriation by resident investors does not always follow suit. Local investors play a meaningful stabilizing role in the face of global risk aversion shocks, with sizeable asset repatriation largely offsetting the retrenchment of non-residents. In contrast, foreign investor retrenchment in response to global monetary policy shocks is not mirrored by asset repatriation. Finally, we find robust evidence that positive global real shocks tend to have a positive impact on net capital inflows to emerging markets. Our results shed light on the likely impact of the Fed's QE tapering on capital flows to emerging market economies.     

Household Life Cycle Protection: Life Insurance Holdings, Financial Vulnerability, and Portfolio Implications

Using the Survey of Consumer Finances, we examine the life cycle demand for different types of life insurance. Specifically, we test for the consumer's aversion to income volatility resulting from the death of a household's wage‐earner through the purchase of life insurance. We first develop a financial vulnerability index to control for the risk to the household. We then examine the life cycle demand for life insurance using several definitions of life insurance. We find, in contrast to previous research, that there is a relationship between financial vulnerability and the amount of term life or total life insurance purchased. In addition, we find older consumers use less life insurance to protect a certain level of financial vulnerability than younger consumers. Secondly, our study provides evidence that life insurance demand is jointly determined as part of a household's portfolio. Finally, we consider the impact of family members' nonmonetary contribution on the household's life cycle protection decision. Our results provide some evidence that households take into account the value of nonmonetary contribution in their insurance purchase.     

Decision making with Expected Shortfall and spectral risk measures: The problem of comparative risk aversion

We analyze spectral risk measures with respect to comparative risk aversion following Arrow (1965) and Pratt (1964) for deterministic wealth, and Ross (1981) for stochastic wealth. We argue that the Arrow–Pratt-concept per se well matches with economic intuition in standard financial decision problems, such as willingness to pay for insurance and simple portfolio problems. Different from the literature, we find that the widely-applied spectral Arrow–Pratt-measure is not a consistent measure of Arrow–Pratt-risk aversion. Instead, the difference between the antiderivatives of the corresponding risk spectra is valid. Within the framework of Ross, we show that the popular subclasses of Expected Shortfall, and exponential and power spectral risk measures cannot be completely ordered with respect to Ross-risk aversion. Thus, for all these subclasses, the concept of Ross-risk aversion is not generally compatible with Arrow–Pratt-risk aversion, but induces counter-intuitive comparative statics of its own. Compatibility can be achieved if asset returns are jointly normally distributed. The general lesson is that these restrictions have to be considered before spectral risk measures can be applied for the purpose of optimal decision making and regulatory issues.     

Optimal Life-Cycle Asset Allocation: Understanding the Empirical Evidence

We show that a life‐cycle model with realistically calibrated uninsurable labor income risk and moderate risk aversion can simultaneously match stock market participation rates and asset allocation decisions conditional on participation. The key ingredients of the model are Epstein–Zin preferences, a fixed stock market entry cost, and moderate heterogeneity in risk aversion. Households with low risk aversion smooth earnings shocks with a small buffer stock of assets, and consequently most of them (optimally) never invest in equities. Therefore, the marginal stockholders are (endogenously) more risk averse, and as a result they do not invest their portfolios fully in stocks.     

A Gentle Introduction to Risk Aversion and Utility Theory

While the topics of risk aversion and utility theory have been discussed extensively in the academic literature on risk and insurance, this literature does not include a pedagogical discussion that is widely accessible for classroom use. This article provides a practical introduction to risk aversion that is designed for readers with little prerequisite course work in economics or statistics. We describe a simple model of insurance demand that can be applied to the property, liability, life, and health insurance markets. We also demonstrate how risk aversion affects a variety of real-life insurance decisions made under conditions of uncertainty, including how much the market will bear to pay for insurance administrative expenses and how demand varies for different types of auto insurance coverage. Exercises and practice problems are provided so that readers can test their mastery of the concepts presented in the article. An instructional note on using this article to teach risk aversion in the classroom is also provided.     

Is Historical Cost Accounting a Panacea? Market Stress,Incentive Distortions,and Gains Trading

Accounting rules, through their interactions with capital regulations, affect financial institutions’ trading behavior. The insurance industry provides a laboratory to explore these interactions: life insurers have greater flexibility than property and casualty insurers to hold speculative‐grade assets at historical cost, and the degree to which life insurers recognize market values differs across U.S. states. During the financial crisis, insurers facing a lesser degree of market value recognition are less likely to sell downgraded asset‐backed securities. To improve their capital positions, these insurers disproportionately resort to gains trading, selectively selling otherwise unrelated bonds with high unrealized gains, transmitting shocks across markets.     

Insurance demand in the presence of loss-dependent background risk

We analyze insurance demand when insurable losses come with an uninsurable zero-mean background risk that increases in the loss size. If the individual is risk vulnerable, loss-dependent background risk triggers a precautionary insurance motive and increases optimal insurance demand. Prudence alone is sufficient for insurance demand to increase in two cases: the case of fair insurance and the case where the smallest possible loss exceeds a certain threshold value (referred to as the large loss case). We derive conditions under which insurance demand increases or decreases in initial wealth. In the large loss case, prudence determines whether changes in the background risk lead to more insurance demand. We generalize this result to arbitrary loss distributions and find conditions based on decreasing third-degree Ross risk aversion, Arrow–Pratt risk aversion, and Arrow–Pratt temperance.     

Organizational structure,risk-based capital requirements,and the sales of downgraded bonds

Using bond downgrades as external shocks to life insurers’ asset risk, we document several findings of the impact of organizational structure and risk factors on investment risk taking. First, we find that mutual insurers and widely-held stock insurers are more likely to sell downgraded bonds than are closely-held stock insurers. Second, we find evidence that insurers are less likely to sell downgraded bonds that remain in the same rating class than bonds downgraded to a lower rating class. The result implies that insurers sell downgraded bonds mainly because of additional capital charge is imposed, not because of downgrade itself. In other words, risk factors in risk-based capital regulation do matter on life insurers’ investment risk taking. Finally, we find that life insurers might be reluctant to sell downgraded bonds at fire-sale prices during the 2008–2009 financial crisis.     

Granular institutional investors and global market interdependence

We study the propagation of global investment risk across markets through the granular view of institutional investors. Applying the conditional value-at-risk estimation to micro-level weekly observations of international mutual funds between 2003 and 2011, we find that idiosyncratic shocks to large institutional investors explain both aggregate market risk and cross-market risk interdependence. Conditional on the US capital markets being in financial distress, idiosyncratic shocks to the top 10% largest funds investing in the US explain about 40% of the risk fluctuations in other non-US markets. The findings are also economically and statistically significant for the top largest funds investing in non-US markets, with the effects becoming especially large during the global financial crisis of 2007–09. These results are robust after controlling for common risk factors and applying alternative measures of idiosyncratic shocks.     

Does operating risk affect portfolio risk? Evidence from insurers' securities holding

This study empirically examines, in the setting of insurance companies, the hypothesis that investors facing more operating risk may behave as if they were more risk averse in investment decisions. Specifically, we study how operating risk from underwriting insurance policies affects insurers' risk taking behavior in their portfolio investments. We find that insurers with higher volatilities in underwriting incomes and cash flows are more conservative in their financial investment risk taking – they have lower credit risk exposure in their bond investments, as well as lower portfolio weights on risky bonds and equities. Further, insurers' portfolio risk exposure is sensitive to the risk of permanent underwriting income shocks but insensitive to the risk of transitory shocks. Transitory operating risk, however, is significantly related to portfolio risk when insurers face tight financing constraints. Our findings suggest a substitutive effect of operating risk on investment decisions by financial institutions.     

Reinsurance decisions in life insurance: An empirical test of the risk–return criterion

Recent studies have analyzed optimal reinsurance contracts within the framework of profit maximization and/or risk minimization. This type of framework, however, does not consider reinsurance as a tool for capital management and financing. In the present paper, we consider different proportional reinsurance contracts used in life insurance (viz., quota-share, surplus, and combinations of quota-share and surplus) while taking into account the insurer's capital constraints. The objective is to determine how different reinsurance transactions affect the risk/reward profile of the insurer and whether factors, such as claims severity, premiums, and insurer's risk appetite, influence the choice of a proportional reinsurance coverage. We compare each reinsurance structure based on actual insurance company data, using the risk–return criterion. This criterion determines the type of reinsurance that enables insurer to retain the largest underwriting profits and/or minimize the risk of the retained claims while keeping the insurer's risk appetite constant, assuming a given capital constraint. The results of this study confirm that the choice of reinsurance arrangement depends on many factors, including risk retention levels, premiums, and the variance of the sum insured values (and therefore claims). As such, under heterogeneous insurance portfolio single type of reinsurance arrangement cannot maximize insurer's returns and/or minimize the risk, therefore a combination of different reinsurance coverages should be employed. Hence, future research on optimal risk management choices should consider heterogeneous portfolios while determining the effects of different financial and risk management tools on companies' risk–return profiles.     

On the Consequences of Behavioral Adaptations in the Cost–Benefit Analysis of Road Safety Measures

It is sometimes argued that road safety measures or automobile safety standards fail to save lives because safer highways or safer cars induce more dangerous driving. A similar but less extreme view is that ignoring the behavioral adaptation of drivers would bias the cost–benefit analysis of a traffic safety measure. This article derives cost–benefit rules for automobile safety regulation when drivers may adapt their risk‐taking behavior in response to changes in the quality of the road network. The focus is on the financial externalities induced by accidents because of the insurance system as well as on the consequences of drivers' risk aversion. We establish that road safety measures are Pareto improving if their monetary cost is lower than the difference between their (adjusted for risk aversion) direct welfare gain with unchanged behavior and the induced variation in insured losses due to drivers' behavioral adaptation. The article also shows how this rule can be extended to take other accident external costs into account.     

Deposit Insurance, Capital Regulations, and Financial Contagion in Multinational Banks

Abstract:  Banking sector globalization has caused an expansion in foreign-owned bank assets. In this paper we analyse the effects of a MNB's liability structure upon its investment in a foreign country. We develop a model in which capital adequacy requirements introduce some deliberate underinvestment which counters deposit insurance-induced overinvestment. Diversification is unattractive with fixed bank capital requirements, because it reduces the expected value of the deposit insurance net. This effect applies in multinational banks (MNBs), where shocks to the home country economy alter the value of the deposit insurance net and hence affect overseas lending incentives. Thus, MNBs act as a channel for financial contagion. We discuss the policy implications of our results.     

Macroeconomic Shocks and Banking Regulation

The recent crisis has brought to the fore the cyclical properties of banking regulation. Countercyclical buffers and enhanced capital requirements meant to stabilize banks’ balance sheets across the cycle are not costless, and a delicate balance needs to be reached between providing incentives to generate value and discouraging excessive risk taking. The paper develops a model in which, in contrast with Modigliani–Miller, outside equity and capital requirements matter. It analyses banking regulation in the presence of macroeconomic shocks and studies the desirability of self‐insurance mechanisms such as countercyclical capital buffers or dynamic provisioning, as well as “macro‐hedges” such as CoCos and capital insurance.     

Dynamic portfolio choice with deferred annuities

We derive the optimal life-cycle portfolio choice and consumption pattern for households facing uncertain labor income, risky capital market, and mortality risk. In addition to stocks and bonds, the households have access to deferred annuities. Deferred payout life annuities are financial contracts providing life-long income to the annuitant after a specified period of time conditional on survival. We find that deferred annuities play an important role in household portfolios and generate significant welfare gains. Households with high benefits from state pensions, moderate risk aversion and moderate labor income risk purchase deferred annuities from age 40 and gradually increase their portfolio share. At retirement, deferred annuities account for 78% of total financial wealth. Households with low state pensions and high labor income risk purchase more annuities and earlier. Uncertainty with respect to future mortality rates has the same effect, i.e. household hedge against longevity risks using deferred annuities.     

Dynamics of Banks' Capital Accumulation

We construct a dynamic neoclassical model of banking capital where the dynamics are governed by the process of financial capital accumulation and credit risk realizations in a structure where stylized banking characteristics are maintained. This is aimed at focusing on how the profit‐maximizing capital ratio of banks evolves and how it reacts to exogenous shocks particularly so during periods of prolonged downturn of the economy. We examine impulse responses of our model to credit risk shock, business cycle shock, and monetary policy shock. The convergence of financial capital to its optimal level is also explored.     

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.     

FX Intervention in the New Keynesian Model

We develop an open-economy New Keynesian Model with foreign exchange (FX) intervention in the presence of a financial accelerator and shocks to risk appetite in international capital markets. We obtain closed-form solutions for optimal monetary and FX intervention policies assuming the central bank cannot commit to future policies, and we compare the solution to that under policy commitment. We show how FX intervention can help reduce the volatility of the exchange rate, of inflation, and of the output gap, thus mitigating welfare losses associated with shocks in the international capital markets. We also show that, when the financial accelerator is strong, there is a risk of indeterminacy (self-fulfilling currency and inflation movements) although FX intervention can reduce this risk and thus reinforce the credibility of the inflation targeting regime. Model simulations match well the impact of a VIX shock obtained by local projections on a panel of inflation targeting emerging markets.