Equilibrium Analysis of Portfolio Insurance

A martingale approach is used to characterize general equilibrium in the presence of portfolio insurance. Insurers sell to noninsurers in bad states, and general equilibrium requires that the risk premium rises to induce noninsurers to increase their holdings. We show that portfolio insurance increases price volatility, causes mean reversion in asset returns, raises the Sharpe ratio and volatility in bad states, and causes volatility to be correlated with volume. We also explain why out-of-the-money S&P 500 put options trade at a higher volatility than do in-the-money puts.     

The Impact of Catastrophes on Insurer Stock Volatility

This article investigates the impact of natural catastrophes and the 9‐11 attacks on (1) the volatility of insurance stocks and (2) the correlation of insurance stocks with the market. We find that natural catastrophes increase the volatility of insurance stocks. They also have a tendency to reduce the correlation of insurance stocks and the market. Investors can, consequently, diversify natural catastrophe risk by additionally holdings of a market portfolio. However, this does not hold for 9‐11. The events of 9‐11 led to increases in volatility and, simultaneously, to an increase in correlation. We also find evidence that 9‐11 increased the beta of insurance stocks.     

On the causes of volatility effects of conglomerate breakups

We describe four channels through which breakups can potentially increase idiosyncratic volatility for parent firms. These are: loss of diversification (portfolio effect), change in growth opportunities, change in operational efficiency, and the flow and assimilation of information (information effect). The relevance of each channel depends on the mode of a breakup. We explain conceptually and show empirically, using a sample of 530 breakups (259 spinoffs and 271 equity carveouts), that the portfolio effect is dominant for spinoff parents, while the information effect gains importance for carveout parents. Our novel insight is that the magnitude of the information effect depends on the pre-announcement information set held by investors; we provide a simple state-space model and empirical evidence to support this intuition. We also find a relation between the change in operational efficiency and the change in idiosyncratic volatility for spinoff parents.     

A general equilibrium model of portfolio insurance

This article examines the effects of portfolio insurance onmarket and asset price dynamics in a general equilibrium continuous-timemodel. Portfolio insurers are modeled as expected utility maximizingagents. Martingale methods are employed in solving the individualagents' dynamic consumption-portfolio problems. Comparisonsare made between the optimal consumption processes, optimallyinvested wealth and portfolio strategies of the portfolio insurersand 'normal agents'. At a general equilibrium level, comparisonsacross economies reveal that the market volatility and riskpremium are decreased, and the asset and market price levelsincreased, by the presence of portfolio insurance.     

Trading with Asymmetric Volatility Spillovers

Abstract:  We study the profitability of trading strategies based on volatility spillovers between large and small firms. By using the Volatility Impulse-Response Function of Lin (1997) and its extensions, we detect that any volatility shock coming from small companies is important to large companies, but the reverse is only true for negative shocks coming from large firms. To exploit these asymmetric patterns in volatility, different trading rules are designed based on the inverse relationship existing between expected return and volatility. We find that most strategies generate excess after-transaction cost profits, especially after very bad news and very good news coming from large or small firm markets. These results are of special interest because of their implications for risk and portfolio management.     

Managerial risk-taking behavior and equity-based compensation

Equity-based compensation affects managers’ risk-taking behavior, which in turn has an impact on shareholder wealth. In response to an exogenous increase in takeover protection in Delaware during the mid-1990s, managers lower firm risk by 6%. This risk reduction is concentrated among firms with low managerial equity-based incentives, in particular firms with low chief executive officer portfolio sensitivity to stock return volatility. Furthermore, the risk reduction is value-destroying. Finally, firms respond to the increased protection accorded by the regime shift by providing managers with greater incentives for risk-taking.     

CEO risk incentives and firm performance following R&D increases

In this study we analyze how CEO risk incentives affect the efficiency of research and development (R&D) investments. We examine a sample of 843 cases in which firms increase their R&D investments by an economically significant amount over the period of 1995–2006. We find that firms with higher sensitivity of CEO compensation portfolio value to stock volatility (vega) are more likely to have large increases in R&D investments. More importantly, we find that high-vega firms experience lower abnormal stock returns and lower operating performance compared to their low-vega counterparts following the R&D increases. Our main results hold in a variety of robustness tests. The results are consistent with the conjecture that high-vega compensation portfolios may induce managers to overinvest in inefficient R&D projects and therefore hurt firm performance.     

Do U.S. Insurance Firms Offer the “Wrong” Incentives to Their Executives?

We examine the relation between executive compensation and market‐implied default risk for listed insurance firms from 1992 to 2007. Shareholders are expected to encourage managerial risk sharing through equity‐based incentive compensation. We find that long‐term incentives and other share‐based plans do not affect the default risk faced by firms. However, the extensive use of stock options leads to higher future default risk for insurance firms. We argue that this is because option‐based incentives induce managerial risk‐taking behavior, which seeks to maximize managerial payoff through equity volatility. This could be detrimental to the interests of shareholders, especially during a financial crisis.     

New ESG rating drivers in the cross-section of European stock returns

We assess the performance of two quantitative signals based on ESG scores across a large, multi-national cross-section of European stock returns. We test whether the cost of equity capital is more influenced by the upward momentum (measured over time) of the ESG scores of the firms issuing stocks or by their stability (identified as the volatility of the scores over time), measured around a changing mean level. We find that short-term ESG momentum over 1 month has a significant impact on the cross-section of stock returns, lowering the anticipated cost of capital and leading to positive average abnormal returns. This suggests that short-term ESG momentum may represent a novel, priced systematic risk factor. Furthermore, we find strong evidence that an ESG volatility spread strategy which buys low ESG score volatility stocks and sells high volatility ones, generates a substantial alpha and affects the ex-ante cost of capital. Both quantitative ESG signals result in portfolio sorting and long-short strategies that enhance the overall sustainability profile of the issuing firms without compromising the raw average of their ESG scores.     

(S,s)-adjustment Strategies and Hedging under Markovian Dynamics

We study the destabilizing effect of hedging strategies under Markovian dynamics with transaction costs. Once transaction costs are taken into account, continuous portfolio rehedging is no longer an optimal strategy. Using a non-optimizing (local in time) strategy for portfolio rebalancing, explicit dynamics for the price of the underlying asset are derived, focusing in particular on excess volatility and feedback effects of these portfolio insurance strategies. Moreover, it is shown how these latter depend on the heterogeneity of the insured payoffs. Finally, conditions are derived under which it may be still reasonable, from a practical viewpoint, to implement Black–Scholes strategies.     

Reinsurance and corporate taxation in the United Kingdom life insurance industry

There are two main tax-related arguments regarding the use of reinsurance – the income volatility reduction and the income level enhancement arguments. The income volatility reduction argument contends that firms facing convex tax schedules have incentives to hedge in order to reduce the volatility of their annual taxable income and thereby lower expected tax liabilities [Smith, C.W., Stulz, R.M., 1985. Optimal hedging policies. Journal of Financial and Quantitative Analysis 19, 127–140]. The income level enhancement argument, advanced by Adiel [Adiel, R., 1996. Reinsurance and the management of regulatory ratios and taxes in the property–casualty insurance industry. Journal of Accounting and Economics 22, 207–240], is more specific to hedging via reinsurance. This perspective holds that reinsurance enhances current reported earnings via the receipt of reinsurance commissions and so increases tax liabilities. Consequently, insurance firms with high marginal tax rates should use less reinsurance than those with low marginal tax rates if tax matters. Prior studies using data on financial derivatives have produced mixed results on the validity of the first argument, while Adiel (1996) finds the second argument insignificant in his study of the use of reinsurance by a sample of United States (US) property–liability insurance firms. This study tests the two tax-related arguments using 1992–2001 data for a sample of United Kingdom (UK) life insurance firms. We find that UK life insurers with low before-planning marginal tax rates tend to use more reinsurance; in contrast, tax convexity is found to have no significant impact on the purchase of reinsurance and so the volatility-reduction argument is not supported.     

Capital and risk in property-liability insurance markets

This paper investigates the capital and portfolio risk decisions of property-liability insurance firms. A theoretical model based on option pricing theory is developed which predicts a positive relationship between insurer capital and risk, as firms balance these two factors to achieve their desired overall insolvency risk. The implications of the model are then tested empirically using a simultaneous equations methodology. The results support the predictions of the model. They also provide evidence that managerial incentives play a role in determining capital and risk in insurance markets. The findings have significant implications for insurance solvency regulation.     

On Valuing Participating Life Insurance Contracts with Conditional Heteroscedasticity

In this paper, we consider a novel approach for the fair valuation of a participating life insurance policy when the dynamics of the reference portfolio underlying the policy are governed by an Asymmetric Power GARCH (APGARCH) model with innovations having a general parametric distribution. The APGARCH model provides a flexible way to incorporate the effect of conditional heteroscedasticity or time-varying conditional volatility and nests a number of important symmetric or asymmetric ARCH-type models in the literature. It also provides a flexible way to capture both the memory effect of the conditional volatility and the asymmetric effects of past positive and negative returns on the current conditional volatility, called the leverage effect. The key valuation tool here is the conditional Esscher transform of Bühlmann et al. (1996, 1998). The conditional Esscher transform provides a convenient and flexible way for the fair valuation under different specifications of the conditional heteroscedastic models. We illustrate the practical implementation of the model using the S&P 500 index as a proxy for the reference portfolio. We also conduct sensitivity analysis of the fair value of the policy with respect to the parameters in the APGARCH model to document the impacts of different conditional volatility models nested in the APGARCH model and the leverage effect on the fair value. The results of the analysis reveal that the memory effect of the conditional volatility has more significant impact on the fair value of the policy than the leverage effect.     

An analysis of risk-based asset allocation and portfolio insurance strategies

This paper compares traditional portfolio insurance strategies with modern risk-based dynamic asset allocation strategies within a currency portfolio context for reserve management. Given the objective of preserving reserve value, the evaluation of the hedging performances of various strategies focuses on four perspectives regarding, in particular, the return distribution of the hedged portfolio. In terms of the Sharpe Ratio, the constant proportional portfolio insurance is the best performer due to having the lowest volatility, while the Value at Risk strategy based upon the normal distribution is the worst due to its having the smallest return. From the perspective that the return distribution of the hedged portfolio is shifted to the right, the synthetic put performs the best, with the expected shortfall strategy the second best. In terms of the cumulative portfolio return across years, the expected shortfall strategy using the historical distribution ranks first, as a result of its participation in upward markets. Furthermore, the expected shortfall-based strategy results in a lower turnover within the investment horizon, thereby saving transaction costs.     

Does futures trading increase stock market volatility? The case of the Nikkei stock index futures markets

We propose new tests to examine whether stock index futures affect stock market volatility. These tests decompose spot portfolio volatility into the cross-sectional dispersion and the average volatility of returns on the portfolio's constituent securities. Our tests show that for Nikkei stocks spot portfolio volatility increased and cross-sectional dispersion decreased compared with average volatility when Nikkei futures began trading on the Osaka Securities Exchange, but not on the Singapore International Monetary Exchange. For non-Nikkei stocks, no shift occurred when futures trading began on either exchange. These findings are consistent with the hypotheses that futures trading increases spot portfolio volatility but that there is no volatility “spillover” to stocks against which futures are not traded. However, the increase in volatility attributable to futures trading is small compared with volatility shifts induced by changes in broad economic factors.     

A model-independent measure of aggregate idiosyncratic risk

This paper introduces a model-independent measure of aggregate idiosyncratic risk, which does not require estimation of market betas or correlations and is based on the concept of gain from portfolio diversification. The statistical results and graphical analyses provide strong evidence that there are significant level and trend differences between the average idiosyncratic volatility measures of Campbell et al. [Campbell, J.Y., Lettau, M., Malkiel, B.G., and Xu, Y., 2001, Have individual stocks become more volatile? An empirical exploration of idiosyncratic risk, Journal of Finance 56, 1–43.] and the new methodology. Although both approaches indicate a noticeable increase in the firm-level idiosyncratic risk, the volatility measure of CLMX is greater and has a stronger upward trend than the new idiosyncratic volatility measure. For both measures of idiosyncratic risk, the upward trend is found to be stronger for smaller, lower-priced, and younger firms. The analytical and empirical results show that the significant upward trend in the differences of the two idiosyncratic volatility measures is related to the increase in the cross-sectional dispersion of the volatility of individual stocks.     

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.     

D&O insurance and IPO performance: What can we learn from insurers?

We investigate whether a firm’s directors’ and officers’ liability insurance contract at the time of the IPO is related to insured firms’ first year post-IPO performance. We find that insurers charge a higher premium per dollar of coverage to protect the directors and officers of firms that will subsequently have poor first year post-IPO stock performance. A higher price of coverage is also associated with a higher post-IPO volatility and lower Sharpe ratio. Our results are robust to various econometric specifications and suggest that even when the high level of information asymmetry inherent to the IPO context prevails, insurers have information about the firms’ prospects that should be valuable to outside investors.     

The forward E/P ratio and earnings growth

Valuation theories predict a negative relation between the earnings-to-price (E/P) ratio and future earnings growth, but prior studies have produced conflicting results. Using a growth measure that incorporates loss firms, this paper shows that the negative relation exists in the long term, but not in the short term. The results also show a U-shaped relation between the forward E/P ratio and earnings risk. Compared with high forward E/P firms which are inherently financially distressed, low forward E/P firms exhibit even higher incidence of loss and larger growth volatility in subsequent years. The wide distribution of earnings growth in the lowest forward E/P portfolio indicates that this portfolio includes not only star firms that generate the strongest earnings growth, but also firms that report the most negative earnings growth. This paper shows that the forward E/P ratio is a stronger predictor of future growth than the conventionally used trailing E/P ratio.