The impact of sovereign credit ratings on Eurobond yields: Evidence from Africa

The importance of sovereign credit ratings and Eurobonds issued by governments have come to the fore in Africa in the last decade. We examine whether changes in sovereign credit ratings impact Eurobond yields in 8 countries over the period of 2014–2019. Our approach reviews rating changes impact on Eurobond yields utilising the event study methodology. Our findings reflect that, on average, close to a third of rating actions directly impact bond yields in African countries. The statistically significant events include the downgrades of South Africa and Namibia to non-investment grade in 2017 reflecting critical transitions and bond investors’ reactions. Overall, the low percentage of a third, relative to previous international studies, suggests that largely rating changes are anticipated, do not have much new information and perhaps the perceived power of credit rating agencies may be overstated. In our view, the results reflect that pre-announcements of rating review dates since 2014 makes rating actions predictable and less impactful to bond yields. In addition, they reflect that bond investors adjust in real time as new information come in, resulting in less reliance on the opinions of CRAs and using their own assessments.     

Firstborn CEOs and credit ratings

Our study examines whether CEOs’ birth order can predict firms’ credit ratings. Consistent with studies that document a positive relationship in the general population between being firstborn and being conservative, our study finds that firms managed by firstborn CEOs tend to have higher credit ratings than those managed by later-born CEOs. Our results are robust to controlling for additional personal CEO traits, such as political identity, and to using a propensity score matching sample. A change analysis supports the causality of the firstborn effect. We suggest that return on assets and free cash flow are possible channels through which firstborn status affects credit ratings. Cross-sectional analyses show that the positive association is less (more) pronounced for firstborn CEOs who have a pilot license (run firms in less competitive industries). These results suggest that managerial conservatism may be an important factor in credit rating agencies’ credit risk assessments.     

Bankruptcy probability changes and the differential informativeness of bond upgrades and downgrades

Prior studies have found that stock returns around announcements of bond upgrades are insignificant, but that stock prices respond negatively to announcements of bond downgrades. This asymmetric stock market reaction suggests either that bond downgrades are timelier than upgrades, or that voluntary disclosures by managers preempt upgrades but not downgrades. This study investigates these conjectures by examining changes in firms’ probabilities of bankruptcy (assessed using bankruptcy prediction models) and voluntary disclosure activity around rating change announcements. The results indicate that the assessed probability of bankruptcy decreases before bond upgrades, but not after. By contrast, the assessed probability of bankruptcy increases both before and after bond downgrades. We also find that controlling for potential wealth-transfer related rating actions, which can impact stock returns differently, does not alter our results. Tests of press releases and earnings forecasts issued by firms suggest that the differential informativeness of upgrades and downgrades is not caused by differences in pre-rating change voluntary disclosures by upgraded and downgraded firms. The results support the hypothesis that downgrades are timelier than upgrades.     

Exploring the components of credit risk in credit default swaps

In this paper, we test the influence of various fundamental variables on the pricing of credit default swaps. The theoretical determinants that are important for pricing credit default swaps include the risk-free rate, industry sector, credit rating, and liquidity factors. We suggest a linear regression model containing these different variables, especially focusing on liquidity factors. Unlike bond spreads which have been shown to be inversely related to liquidity (i.e., the greater the liquidity, the lower the spread), there is no a priori reason that the credit default swap spread should exhibit the same relationship. This is due to the economic characteristics of a credit default swap compared to a bond. Our empirical result shows that all the fundamental variables investigated have a significant effect on the credit default swap spread. Moreover, our findings suggest that credit default swaps that trade with greater liquidity have a wider credit default swap spread.     

The (un)informative value of credit rating announcements in small markets

This work examines the information value of local Israeli credit rating announcements. This matter is also important to other small markets, in which a debt issuer may take advantage of a “rating shopping” process or choose to avoid a rating procedure altogether, because the agencies do not carry out unsolicited rating. We analyze the bond and equity markets response to various rating announcements at different time periods. We find that except for downgrades in 2008–2009 the rating announcements have no information value. It seems that generally the market internalizes most of the information prior to the rating announcements.     

Selecting credit rating models: a cross-validation-based comparison of discriminatory power

In commercial banking, various statistical models for corporate credit rating have been theoretically promoted and applied to bank-specific credit portfolios. In this paper, we empirically compare and test the performance of a wide range of parametric and nonparametric credit rating model approaches in a statistically coherent way, based on a ‘real-world’ data set. We repetitively (k times) split a large sample of industrial firms’ default data into disjoint training and validation subsamples. For all model types, we estimate k out-of-sample discriminatory power measures, allowing us to compare the models coherently. We observe that more complex and nonparametric approaches, such as random forest, neural networks, and generalized additive models, perform best in-sample. However, comparing k out-of-sample cross-validation results, these models overfit and lose some of their predictive power. Rather than improving discriminatory power, we perceive their major contribution to be their usefulness as diagnostic tools for the selection of rating factors and the development of simpler, parametric models.

The relationship between liquidity risk and credit risk in banks

This paper investigates the relationship between the two major sources of bank default risk: liquidity risk and credit risk. We use a sample of virtually all US commercial banks during the period 1998–2010 to analyze the relationship between these two risk sources on the bank institutional-level and how this relationship influences banks’ probabilities of default (PD). Our results show that both risk categories do not have an economically meaningful reciprocal contemporaneous or time-lagged relationship. However, they do influence banks’ probability of default. This effect is twofold: whereas both risks separately increase the PD, the influence of their interaction depends on the overall level of bank risk and can either aggravate or mitigate default risk. These results provide new insights into the understanding of bank risk and serve as an underpinning for recent regulatory efforts aimed at strengthening banks (joint) risk management of liquidity and credit risks.     

Sovereign risk assessment and agency credit ratings

Sovereign ratings are gaining importance as more governments with greater default risk borrow in international bond markets. However, while the ratings have proved useful to governments seeking market access, the difficulty of assessing sovereign risk has led to agency disagreements and public controversy over specific rating assignments. Recognising this difficulty, the financial markets have shown some scepticism toward sovereign ratings when pricing issues.     

Contagion effect on bond portfolio risk measures in a hybrid credit risk model

This paper illustrates how modelling the contagion effect among assets of a given bond portfolio changes the risk perception associated to it. This empirical work is developed in a hybrid credit risk framework that incorporates recovery rate risk. Dependence structures among firms and between external shocks affecting firms together are considered. The presence of correlations among firm leverage ratios and the interrelation between default probabilities and recovery rates produces clusters of defaults with low recovery rates. This has a major impact on standard risk measures such as Value-at-Risk and conditional tail expectation. Consequently, an appropriate measurement of the contagion has a tremendous effect on the capital requirement of many financial institutions.     

Modeling the business risk of financially weakened firms: A new approach for corporate bond pricing

Most structural models of default risk assume that the firm's asset return is normally distributed, with a constant volatility. By contrast, this article details the properties that the process of assets should have in the case of financially weakened firms. It points out that jump-diffusion processes with time-varying volatility provide a refined and accurate perspective on the business risk dimension of default risk. Representative Arrow-Debreu state price densities (SPD) and term structures of credit spreads are then explored. The credit curves show that the business uncertainties play a major in the pricing of corporate liabilities.     

Credit ratings and IPO pricing

We examine the effects of credit ratings on IPO pricing. The evidence from U.S. common share IPOs during 1986–2004 shows that when firms go public, those with credit ratings are underpriced significantly less than firms without credit ratings. Credit rating levels, however, do not have a significant effect on IPO underpricing. The existence of credit rating reduces uncertainty about firm value. It is the value certainty that matters, not the value per se. Credit ratings also reduce the degree of price revision during the bookbuilding process and the aftermarket volatility in the post-IPO period. The evidence suggests that credit ratings convey useful information in reducing value uncertainty of the issuing firms as well as information asymmetry in the IPO markets.     

Credit ratings and the cross-section of stock returns

Low credit risk firms realize higher returns than high credit risk firms. This is puzzling because investors seem to pay a premium for bearing credit risk. The credit risk effect manifests itself due to the poor performance of low-rated stocks (which account for 4.2% of total market capitalization) during periods of financial distress. Around rating downgrades, low-rated firms experience considerable negative returns amid strong institutional selling, whereas returns do not differ across credit risk groups in stable or improving credit conditions. The evidence for the credit risk effect points towards mispricing generated by retail investors and sustained by illiquidity and short sell constraints.     

Counterparty credit risk and the credit default swap market

Counterparty credit risk has become one of the highest-profile risks facing participants in the financial markets. Despite this, relatively little is known about how counterparty credit risk is actually priced. We examine this issue using an extensive proprietary data set of contemporaneous CDS transaction prices and quotes by 14 different CDS dealers selling credit protection on the same underlying firm. This unique cross-sectional data set allows us to identify directly how dealers' credit risk affects the prices of these controversial credit derivatives. We find that counterparty credit risk is priced in the CDS market. The magnitude of the effect, however, is vanishingly small and is consistent with a market structure in which participants require collateralization of swap liabilities by counterparties.     

Information risk and credit contagion

This paper demonstrates a positive relationship between information risk and the credit contagion effect. We use abnormal changes in the Credit Default Swaps (CDS) spreads to measure the contagion effect, and the dispersion of analyst forecasts as a proxy for information risk. We find that firms with higher information risk suffer a greater contagion effect that occurs in advance to the credit default events. This finding is robust under controls of key firm-specific characteristics and general condition of stock and credit markets.     

A Multicriteria Approach for Modeling Small Enterprise Credit Rating: Evidence from China

ABSTRACT

As the engine of China’s economy, small enterprises have been the central to the country’s economic development. However, given the characteristics of the small enterprises loan (i.e., short borrowing period, large volume, small amount and incomplete information), it is extremely challenging for financial institutions to assess their creditworthiness. Thus, it seriously delays and restricts the financing access for small enterprises. In an attempt to relieve the financing difficulty of small enterprises, this article makes use of 687 small wholesale and retail enterprises in a regional commercial bank in China, to establish a credit rating indicator system composed of 17 indicators by using both partial correlation analysis and probit regression. It then utilizes TOPSIS together with fuzzy C-means to score the credit ratings of our sample of small enterprises. With the dual test of default discrimination and ROC curve, the prediction accuracy of the established indicator system has reached 80.10% and 0.917, respectively, indicating the robustness and validity of our credit rating system.     

Empirical credit cycles and capital buffer formation

We model 1927–1997 US business failure rates using an unobserved components time series model. Clear evidence is found of cyclical behavior in default rates. We also detect significant longer term movements in default rates and default correlations. In a multi-year backtest experiment we show that accommodation of default rate dynamics has important consequences for credit risk capitalization requirements. Static or myopic variants of credit portfolio models miss significant periods of credit risk accumulation. Empirically congruent dynamic models by contrast provide more timely warning signals of credit risk build-up. In this way they may mitigate some of the pro-cyclicality concerns.     

Up and down credit risk

This paper discusses the main modeling approaches that have been developed for handling portfolio credit derivatives, with a focus on the question of hedging. In particular, the so-called top, top down and bottom up approaches are considered. We give some mathematical insights regarding the fact that information, namely the choice of a relevant model filtration, is the major modeling issue. In this regard, we examine the notion of thinning that was recently advocated for the purpose of hedging a multi-name derivative by single-name derivatives. We then illustrate by means of numerical simulations (semi-static hedging experiments) why and when the portfolio loss process may not be a ‘sufficient statistic’ for the purpose of valuation and hedging of portfolio credit risk.     

Accounting data and the credit spread: An empirical investigation

Measures of credit risk based on Merton (1974) rely upon information available in the market prices of securities. Under the Efficient Market Hypothesis market prices should reflect all available information and, hence, make redundant all other information in the analysis of credit risk. This paper examines whether accounting data are fully reflected in the market-based measures of credit risk and therefore has no role in explaining variations in the credit spread on corporate bonds. We use a sample consisting of over 11,000 firm-quarter observations with matched equity, bond and accounting data. The results suggest that equity volatility and Merton's distance-to-default outperform accounting variables in explaining variations in the credit spread. However, accounting variables are incrementally informative in explaining variations in the credit spread when considered in conjunction with market-based measures. Within the set of accounting variables considered, we find that the profitability ratio is by far the most incrementally informative accounting variable.     

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.     

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.