Knowledge that Transforms

This paper provides an economic and mathematical characterization of operational risk useful for clarifying the issues related to estimation and the determination of economic capital. The insights for this characterization originate in the corporate finance literature. Operational risk is subdivided into two types, either: (i) the risk of a loss due to the firm’s operating technology, or (ii) the risk of a loss due to agency costs. These two types of operational risks generate loss processes with different economic characteristics. We argue that the current methodology for the determination of economic capital for operational risk is overstated. It is biased high because the computation omits the bank’s net present value (NPV) generating process. We also show that although it is conceptually possible to estimate the operational risk processes’ parameters using only market prices, the non-observability of the firm’s value makes this an unlikely possibility, except in rare cases. Instead, we argue that data internal to the firm, in conjunction with standard hazard rate estimation procedures, provides a more fruitful alternative.

This paper examines whether bank holding company (BHC) risk ratings are asymmetrically assigned or biased over business cycles from 1986 to 2003. In a model of ratings determination which accounts for bank characteristics, financial market conditions, past supervisory information, and aggregate macro-economic factors, we find that bank exam ratings exhibit inter-temporal characteristics. First, exam ratings exhibit some evidence of examiner bias for several periods analyzed. When the business cycle turns, examiners sometime depart from standards that they set during the previous phases of the cycle. However, this bias is not widespread or systematic. Second, exam ratings exhibit some inertia. Our results suggest that examiners rate on the side of not changing (rather than upgrading or downgrading) an institution’s exam rating. Third, we find robust evidence of a secular trend towards more stringent examination BHC ratings standards over time.

The aim of the paper is to analyze the diversification effect brought by crude oil Futures contracts, the most liquid commodity Futures, into a portfolio of stocks. The studies that have documented the very low- and essentially negative-correlations between commodities and equities typically rely on normally distributed returns, which is not the case for crude oil Futures and stocks indexes. Moreover, the particular time-to-maturity chosen for the Future contract used as an investment vehicle is an important matter that needs to be addressed, in presence of forward curves switching between backwardation and contango shapes. Our goal in this paper is twofold: (a) we introduce copula functions to have a better representation of the dependence structure of oil Futures with equity indexes; (b) using this copula representation, we are able to analyze in a precise manner the “maturity effect” in the choice of crude oil Future contract with respect to its diversification benefits. Our finding is that, in the case of distant maturities Futures, e.g., 18 months, the negative correlation effect is more pronounced whether stock prices increase or decrease. This property has the merit to avoid the hurdles of a frequent roll over while being quite desirable in the current trendless equity markets. Empirical evidence is exhibited on a database comprising the NYMEX WTI crude oil Futures and S&P 500 index over a 15 year-time period.

We investigate the equity market timing hypothesis of capital structure in major industrialized (G-7) countries. As claimed by its proponents, we find that leverage of firms is negatively related to the historical market-to-book ratio in all G-7 countries. However, this negative relationship cannot be attributed to equity market timing. We find no association between equity issues and market-to-book ratios at the time of equity financing decisions by Japanese firms. Firms in all G-7 countries, except Japan, undo the effect of equity issuance and the impact of equity market timing attempts on leverage is short lived. This is inconsistent with the prediction of the equity market timing hypothesis and more in line with dynamic trade-off model.

This paper analyzes the important time variation in US aggregate household portfolios. To do so, we first use flexible descriptions of preferences and investment opportunities to derive household optimal decision rules that nest static, myopic, and non-myopic portfolio allocations. We then compare these rules to the data through formal statistical analysis. Our main results reveal that: (i) static and myopic investment behaviors are rejected, (ii) non-myopic portfolio allocations are supported, and (iii) the Fama–French factors best explain empirical portfolio shares.

Despite mounting evidence to the contrary, credit migration matrices, used in many credit risk and pricing applications, are typically assumed to be generated by a simple Markov process. Based on empirical evidence, we propose a parsimonious model that is a mixture of (two) Markov chains, where the mixing is on the speed of movement among credit ratings. We estimate this model using credit rating histories and show that the mixture model statistically dominates the simple Markov model and that the differences between two models can be economically meaningful. The non-Markov property of our model implies that the future distribution of a firm’s ratings depends not only on its current rating but also on its past rating history. Indeed we find that two firms with identical current credit ratings can have substantially different transition probability vectors. We also find that conditioning on the state of the business cycle or industry group does not remove the heterogeneity with respect to the rate of movement. We go on to compare the performance of mixture and Markov chain using out-of-sample predictions.

In this paper, we develop and test a model of implicit recourse in asset-backed securitizations. Fraud losses on securitized assets are generally incurred by the bank and do not affect the performance of securitization trusts, while credit losses do affect the trust’s performance and are potentially borne by the owner of the securitized assets. Thus, the classification of losses as either fraud or credit losses provides a potential avenue of implicit recourse to manipulate the performance of securitization trusts. Using annual data from 2001 to 2006, we find that the performance of the credit card securitization portfolio is negatively related to fraud losses reported by the bank. We examine these results in light of the proposed Basel II capital rules and argue that a bank’s incentive to provide implicit recourse will increase under the anticipated regime.

In this paper we theoretically and empirically examine the interaction between hedging, financing, and investment decisions. A simple equilibrium model with costly financial distress suggests that as firms become more efficient at risky investments vis a vis low risk investments, they will borrow less, invest more in risky assets, and hedge more. The model also predicts a positive relationship between hedging and leverage – a result consistent with debt capacity arguments. We test the model empirically using a simultaneous equations framework to investigate the determinants of firm-level hedging, financing and investing decisions. The results strongly support the hypothesis that the hedging, financing and investment decisions are jointly determined. In addition, we find strong support for the central hypothesis that firms more efficient investing in risky technologies more aggressively hedge and use less debt financing in order to maximize their comparative advantage.

By using a different derivation scheme, a new class of two-sided coherent risk measures is constructed in this paper. Different from existing coherent risk measures, both positive and negative deviations from the expected return are considered in the new measure simultaneously but differently. This innovation makes it easy to reasonably describe and control the asymmetry and fat-tail characteristics of the loss distribution and to properly reflect the investor’s risk attitude. With its easy computation of the new risk measure, a realistic portfolio selection model is established by taking into account typical market frictions such as taxes, transaction costs, and value constraints. Empirical results demonstrate that our new portfolio selection model can not only suitably reflect the impact of different trading constraints, but find more robust optimal portfolios, which are better than the optimal portfolio obtained under the conditional value-at-risk measure in terms of diversification and typical performance ratios.

This study finds significant changes in capital market measures of risk following the passage of Sarbanes-Oxley for US financial services firms. Shorter-term measures of risk shifts are positive, on average, and consistent with the mandatory nature of the disclosure and governance provisions. Longer-term total and unsystematic risk shifts are negative, on average, and consistent with reductions in investor uncertainty as transparency improved. We find that the changes in shorter-term and longer-term risk measures vary inversely with the strength of disclosure and governance characteristics. The financial market rewarded (punished) firms with stronger (weaker) disclosure and stronger (weaker) governance.