Interacting particle systems for the computation of rare credit portfolio losses

In this paper, we introduce the use of interacting particle systems in the computation of probabilities of simultaneous defaults in large credit portfolios. The method can be applied to compute small historical as well as risk-neutral probabilities. It only requires that the model be based on a background Markov chain for which a simulation algorithm is available. We use the strategy developed by Del Moral and Garnier in (Ann. Appl. Probab. 15:2496–2534, 2005) for the estimation of random walk rare events probabilities. For the purpose of illustration, we consider a discrete-time version of a first passage model for default. We use a structural model with stochastic volatility, and we demonstrate the efficiency of our method in situations where importance sampling is not possible or numerically unstable.      

Cross-border interbank networks,banking risk and contagion

Recent events have highlighted the role of cross-border linkages between banking systems in transmitting local developments across national borders. This paper analyzes whether international linkages in interbank markets affect the stability of interconnected banking systems and channel financial distress within a network consisting of banking systems of the main advanced countries for the period 1994–2012. Methodologically, I use a spatial modeling approach to test for spillovers in cross-border interbank markets. The results suggest that foreign exposures in banking play a significant role in channeling banking risk: I find that countries that are linked through foreign borrowing or lending positions to more stable banking systems abroad are significantly affected by positive spillover effects. From a policy point of view, this implies that in stable times, linkages in the banking system can be beneficial, while they have to be taken with caution in times of financial turmoil affecting the whole system.     

Cyclical fiscal policy,credit constraints,and industry growth

What are the effects of cyclical fiscal policy on industry growth? We show that industries with a relatively heavier reliance on external finance or lower asset tangibility tend to grow faster (in terms of both value added and of labor productivity growth) in countries that implement fiscal policies that are more countercyclical. We reach this conclusion using Rajan and Zingales׳s (1998) difference-in-difference methodology on a panel data sample of manufacturing industries across 15 OECD countries over the period 1980–2005.     

Understanding liquidity and credit risks in the financial crisis

This paper develops a structured dynamic factor model for the spreads between London Interbank Offered Rate (LIBOR) and overnight index swap (OIS) rates for a panel of banks. Our model involves latent factors which reflect liquidity and credit risk. Our empirical results show that surges in the short term LIBOR-OIS spreads during the 2007-2009 financial crisis were largely driven by liquidity risk. However, credit risk played a more significant role in the longer term (twelve-month) LIBOR-OIS spread. The liquidity risk factors are more volatile than the credit risk factor. Most of the familiar events in the financial crisis are linked more to movements in liquidity risk than credit risk.     

Optimal credit risk transfer, monitored finance, and banks

We examine the implications of optimal credit risk transfer (CRT) for bank-loan monitoring, and the incentives for banks to engage in optimal CRT. In our model, properly designed CRT instruments allow banks to insure themselves against loan losses precisely in those states that signal monitoring. We find that optimal CRT enhances loan monitoring and expands financial intermediation, in contrast to the findings of the previous literature. Optimal CRT instruments are based on loan portfolios rather than individual loans and have credit-enhancement guarantees, pretty much as banks do in practice. But the extent of credit enhancement needs to be precisely delimited. Above that exact level, monitoring incentives are undermined (loan quality deteriorates) and wealth is transferred from the bank's financiers to the bank. Properly designed risk-based capital requirements are shown to prevent such a wealth transfer and to provide banks with the incentive to engage in optimal CRT.     

Estimating Default Probabilities of CMBS Loans with Clustering and Heavy Censoring

This paper provides a comprehensive default estimation of commercial real estate loans with a complete commercial mortgage backed securities (CMBS) loan history database. Standard survival models assume that eventually every observation will experience the event. However, often there is a high proportion of censored observation in the sample. A mixture model is proposed to disentangle the probability of “long-term survivorship” and the timing of default occurrence. Loans within the same geographical area and property type tend to exhibit correlation in default incidence. A multilevel model is proposed to capture this correlation within and between clusters.

Flexible distribution functions,higher-order preferences and optimal portfolio allocation

In this paper we show that flexible probability distribution functions, in addition to being able to capture stylized facts of financial returns, can be used to identify pure higher-order effects of investors' optimizing behavior. We employ the five-parameter weighted generalized beta of the second kind distribution—and other density functions nested within it—to determine the conditions under which risk averse, prudent and temperate agents are diversifiers in the standard portfolio choice theory. Within this framework, we illustrate through comparative statics the economic significance of higher-order moments in return distributions.     

Monotonicity in asset returns: New tests with applications to the term structure,the CAPM,and portfolio sorts

Many theories in finance imply monotonic patterns in expected returns and other financial variables. The liquidity preference hypothesis predicts higher expected returns for bonds with longer times to maturity; the Capital Asset Pricing Model (CAPM) implies higher expected returns for stocks with higher betas; and standard asset pricing models imply that the pricing kernel is declining in market returns. The full set of implications of monotonicity is generally not exploited in empirical work, however. This paper proposes new and simple ways to test for monotonicity in financial variables and compares the proposed tests with extant alternatives such as t-tests, Bonferroni bounds, and multivariate inequality tests through empirical applications and simulations.     

Art as an investment: risk, return and portfolio diversification in major painting markets

The present paper examines risk, return and the prospects for portfolio diversification among major painting and financial markets over the period 1976–2001. The art markets examined are Contemporary Masters, French Impressionists, Modern European, 19th Century European, Old Masters, Surrealists, 20th Century English and Modern US paintings. The financial markets comprise US Treasury bills, corporate and government bonds and small and large company stocks. In common with the published literature in this area, the present study finds that the returns on paintings are much lower and the risks much higher than conventional investment markets. Moreover, while low correlations of returns suggest that opportunities for portfolio diversification in art works alone and in conjunction with equity markets exist, the construction of Markowitz mean‐variance efficient portfolios indicates that no diversification gains are provided by art in financial asset portfolios. However, diversification benefits in portfolios comprised solely of art works are possible, with Contemporary Masters, 19th Century European, Old Masters and 20th Century English paintings dominating the efficient frontier during the period in question.     

Macroeconomic dynamics in a model of goods,labor, and credit market frictions

Goods market frictions drastically change the dynamics of the labor market, both in terms of persistence and volatility. In a model with three imperfect markets – goods, labor, and credit – we find that credit and goods market imperfections are substitutable in raising volatility. Goods market frictions are unique in generating persistence. Two key mechanisms in the goods market generate large hump-shaped responses to productivity shocks: countercyclical goods market tightness and prices alter future profit flows and raise persistence; procyclical search effort of consumers and firms raises amplification. Goods market frictions are thus key in understanding labor market dynamics.     

Growth options,macroeconomic conditions,and the cross section of credit risk

This paper develops a structural equilibrium model with intertemporal macroeconomic risk, incorporating the fact that firms are heterogeneous in their asset composition. Compared with firms that are mainly composed of invested assets, firms with growth options have higher costs of debt because they are more volatile and have a greater tendency to default during recession when marginal utility is high and recovery rates are low. Our model matches empirical facts regarding credit spreads, default probabilities, leverage ratios, equity premiums, and investment clustering. Importantly, it also makes predictions about the cross section of all these features.     

Financial innovation,the discovery of risk,and the U.S. credit crisis

Financial innovation and overconfidence about the risk of new financial products were key factors behind the 2008 U.S. credit crisis. We show that a model with a collateral constraint in which learning about the risk of a new financial environment interacts with Fisherian amplification produces a boom–bust cycle in debt, asset prices and consumption. Early realizations of a high-borrowing-ability regime turn agents optimistic about the persistence probability of this regime. Conversely, the first realization of a low-borrowing-ability regime turns agents unduly pessimistic. The model predicts large increases in household debt, land prices and excess returns during 1998–2006 followed by a collapse.     

Risk-based portfolio strategy in emerging stock markets: economic significance from Brazil,Russia, India and China

The purpose of this paper is to examine the conditional volatility and correlation predictability of four emerging stock markets, and address the issue whether investors could exploit this predictability to earn excess returns from the minimum variance portfolio of index component stocks. Inevitably, transaction cost affects the conclusive results. Nevertheless, economic gain exceeding a conservatively high transaction cost could be derived from a number of conditional volatility and correlation models. One dominant model, the shrinkage model, outperforms the market across the countries, cost structures and performance measures. We also document the superiority of averaging methodologies. However, semiparametric modelling falls in a grey area of profitability – sometimes attractive whilst sometimes not attractive.