The information content of three credit ratings: the case of European residential mortgage-backed securities

We assess the information content of three credit ratings for tranches of newly issued European residential mortgage-backed securities. We find that tranches rated by three credit rating agencies where the rating by Standard & Poor's (S&P's) Ratings Service or Fitch is inferior to Moody's lead to higher funding costs and reflects what we refer to as rating risk. Our results suggest that market participants do not view credit ratings by Fitch and S&P's as redundant despite the fact that both employ the same rating approach.     

Do Rating Agencies Benefit from Providing Higher Ratings? Evidence from the Consequences of Municipal Bond Ratings Recalibration

We ask whether credit rating agencies receive higher fees and gain greater market share when they provide more favorable ratings. To investigate this question, we use the 2010 rating scale recalibration by Moody's and Fitch, which increased ratings absent any underlying change in issuer credit quality. Consistent with prior research, we find that the recalibration allowed the clients of Moody's and Fitch to receive better ratings and lower yields. We add to this evidence by showing that the recalibration also led to larger fees and to increases in the market shares of Moody's and Fitch. These results are consistent with critics’ concerns about the effects of the issuer‐pay model on the credit ratings market.     

Ratings Competition in the CMBS Market

We consider the relationship between competition among credit rating agencies and the ratings of commercial mortgage‐backed securities (CMBS) using data from 2002 to 2007. We characterize competition using Fitch's aggregate share of CMBS ratings and a measure of Fitch's deal‐specific market share constructed as the probability of Fitch being hired for a specific transaction. Controlling for deal characteristics, we find that subordination levels were lower when Fitch's aggregate and deal‐specific market shares were higher, which suggests that ratings competition yielded less stringent ratings when Fitch was a more significant competitor, although this effect dissipates when Fitch's market shares were high.     

A Comparison of Bond Ratings from Moody's S&P and Fitch IBCA

Previous research has found that the bond market values the ratings of Moody's and Standard & Poor's. This paper extends earlier research by comparing the ratings of Moody's, Standard and Poor's, and Fitch IBCA. The authors examine a very large database with monthly observations of bonds and bond ratings over a five‐year time period. The analysis focuses on comparing rating levels, rating changes, and the impact of ratings on bond yields. The results show that firms with publicly available Fitch IBCA ratings have higher ratings from Moody's and S&P than firms without Fitch IBCA ratings. The typical firm releasing a Fitch IBCA rating has a lower yield (controlling for Moody's and S&P rating), a more stable rating, and is more likely to receive an upgrade. For split‐rated bonds (Moody's vs. S&P), Fitch IBCA serves as a tiebreaker. This evidence is consistent with the bond market valuing the ratings of all three raters—Moody's, Standard & Poor's, and Fitch IBCA.     

Sovereign rating actions and the implied volatility of stock index options

This paper examines the interaction between the equity index option market and sovereign credit ratings. S&P and Moody's signals exhibit strong impact on option-implied volatility while Fitch's influence is less significant. Moody's downgrades reduce the market uncertainty over the rated countries' equity markets. Strong causal relationships are found between movements in the option-implied volatility and all credit signals released by S&P and Fitch, but only actual rating changes by Moody's, implying differences in rating agencies' policies. The presence of additional ratings tends to reduce market uncertainty. The findings highlight the importance of rating information in the price discovery process and offer policy implications.     

Competition in the credit rating Industry: Benefits for investors and issuers

We empirically investigate the benefits of multiple ratings not only at issuance of debt instruments but also during the subsequent monitoring phase. Using a record of monthly credit rating migration data on all U.S. residential mortgage-backed securities rated by Standard & Poor's, Moody's, and Fitch between 1985 and 2012 (154,600 tranches), our results provide empirical evidence that rating agencies put more effort in rating and outlook revisions when tranches have assigned multiple ratings. Furthermore, we see that in the case of multiple ratings, agencies do a better job in discriminating tranches with respect to default risk. On the downside, we observe a shift in collateral towards senior tranches and incentives for issuers to engage in rating shopping activities, but find no evidence that rating agencies exploit such behavior to attract more rating business. Our results contribute to the literature on information production of credit ratings and extend the perspective to the monitoring period after issuance.     

Rating Agency Reputation,the Global Financial Crisis,and the Cost of Debt

Why do foreign firms obtain credit ratings by global rating agencies rather than from their home country's rating agencies even though global raters typically assign lower credit ratings when these foreign firms issue bonds in their home currencies? We find that bonds rated by a global agency decreased yields 11‐14 basis points (bps) when compared to those rated by Japanese rating agencies but, during the 2007‐2009 financial crisis, the yields on these Japanese bonds increased 12‐17 bps, thus fully negating the advantage of obtaining a bond rating from a global rater. This suggests that the reputation of global rating agencies declined during the 2007‐2009 crisis period.     

Moody's and S&P Ratings: Are They Equivalent? Conservative Ratings and Split Rated Bond Yields

We examine the relative impact of Moody's and S&P ratings on bond yields and find that at issuance, yields on split rated bonds with superior Moody's ratings are about 8 basis points lower than yields on split rated bonds with superior S&P ratings. This suggests that investors differentiate between the two ratings and assign more weight to the ratings from Moody’s, the more conservative rating agency. Moody's becomes more conservative after 1998 and the impact of a superior Moody's rating becomes stronger. Furthermore, the differential impact of the two ratings is more pronounced for the more opaque Rule 144A issues.     

The ordered qualitative model for credit rating transitions

Information on the expected changes in credit quality of obligors is contained in credit migration matrices which trace out the movements of firms across ratings categories in a given period of time and in a given group of bond issuers. The rating matrices provided by Moody's, Standard & Poor's and Fitch became crucial inputs to many applications, including the assessment of risk on corporate credit portfolios (CreditVar) and credit derivatives pricing. We propose a factor probit model for modeling and prediction of credit rating matrices that are assumed to be stochastic and driven by a latent factor. The filtered latent factor path reveals the effect of the economic cycle on corporate credit ratings, and provides evidence in support of the PIT (point-in-time) rating philosophy. The factor probit model also yields the estimates of cross-sectional correlations in rating transitions that are documented empirically but not fully accounted for in the literature and in the regulatory rules established by the Basle Committee.     

THE INFORMATIONAL CONTENT OF BOND RATINGS

This paper explores the risk structure of interest rates. The focus is on whether yields on industrial bonds indicate that market participants base their evaluations of a bond issue's default risk on agency ratings or on publicly available financial statistics. Using a non-linear least squares procedure, the yield-to-maturity is related to Moody's rating, Standard and Poor's (S&P) rating, and accounting measures of creditworthiness such as coverage and leverage. Market yields are found to be significantly correlated with both the ratings and a set of readily available financial accounting statistics. These results indicate (1) that market participants base their evaluations of an issue's creditworthiness on more than the agencies' ratings and (2) that the ratings bring some information to the market above and beyond that contained in the set of accounting variables. The paper also asks whether the market views Moody's and Standard and Poor's ratings as equally reliable measures of risk or whether the market attaches more weight to one agency's ratings than the other. Finally, the hypothesis that the market pays more attention to the accounting measures and less to the ratings if the rating has not been reviewed recently is tested.     

SPLIT RATINGS,BOND YIELDS,AND UNDERWRITER SPREADS

A split bond rating occurs when Moody's and Standard & Poor give different ratings to the same issue. We examine 1,277 public industrial bond issues, where 221 have split ratings, issued from 1980 through mid-1993. For split-rated industrial bonds, neither rating agency consistently gives higher ratings. Earlier studies find yields for split-rated bonds to be priced as either the higher or the lower of the ratings. We find the yields on split-rated bonds to be an average of the yields on the two ratings. Split ratings for industrial bonds appear to reflect random differences on the part of rating agencies. Our results differ from previous studies because we use a substantially larger sample and include high-yield bonds. As long as a bond has an investment-grade rating, the underwriter fees are found to be essentially the same for all rating categories. Below investment grade, the rating substantially affects the underwriter fee. Thus, split ratings for high-yield bonds have an important effect on the underwriter spread.     

Cross‐Listed Bonds,Information Asymmetry,and Conservatism in Credit Ratings

We propose information asymmetry as an additional explanation for rating conservatism. Because information asymmetry is likely higher for cross‐listed bonds than for U.S. bonds, we expect and find that cross‐listed bonds are rated more conservatively than U.S. domestic bonds at issuance. Further, cross‐listed bonds receive less frequent upgrades and take longer to be upgraded after issuance. Because lower ratings might also reflect higher default risk based on agencies’ private information, we conduct additional tests to discriminate between the rating conservatism and private information explanations. The results are consistent with ratings conservatism and inconsistent with the private information explanation.     

Market Implied Ratings and Financing Constraints: Evidence from US Firms

Financing constraints have been found to play an important role in several aspects of firm behavior, but no attention has been given to their effects on credit ratings. In this paper we analyze a unique and comprehensive data set for US firms rated by Fitch over the period 2001–07. We employ Fitch's market implied ratings derived from bond and equity prices. The analysis finds evidence that financial variables are more important in predicting credit ratings for firms likely to face financing constraints. We conclude that the financing constraint is an important dimension in the market implied ratings process. Our findings are of relevance to managers, investors and rating agencies seeking to understand the mechanism through which financing constraints affect credit ratings.     

Does it matter who pays for bond ratings? Historical evidence

We test whether Standard and Poor's (S&P) assigns higher bond ratings after it switches from investor-pay to issuer-pay fees in 1974. Using Moody's rating for the same bond as a benchmark, we find that when S&P charges investors and Moody's charges issuers, S&P's ratings are lower than Moody's. Once S&P adopts issuer-pay, its ratings increase and no longer differ from Moody's. More importantly, S&P only assigns higher ratings for bonds that are subject to greater conflicts of interest, measured by higher expected rating fees or lower credit quality. These findings suggest that the issuer-pay model leads to higher ratings.     

Variations in sovereign credit quality assessments across rating agencies

We investigate agency variation in credit quality assessment (Standard and Poor’s vs. Moody’s vs. Fitch) employing sovereign ratings data for 129 countries, spanning the period 1990–2006. While we find that the credit rating agencies often disagree about credit quality, it is usually confined to one or two notches on the finer scale. We find that several variables have varying importance in explaining ratings across agencies which leads us to conclude that material heterogeneity exists between them. Also, while watch and outlook procedures are generally strong predictors of rating changes relative to other public data, additional significant variables suggest that it might be possible to augment these agency data to provide better forecasts of future rating changes.     

How did increased competition affect credit ratings?

The credit rating industry has historically been dominated by just two agencies, Moody's and Standard & Poor's, leading to long-standing legislative and regulatory calls for increased competition. The material entry of a third rating agency (Fitch) to the competitive landscape offers a unique experiment to empirically examine how increased competition affects the credit ratings market. What we find is relatively troubling. Specifically, we discover that increased competition from Fitch coincides with lower quality ratings from the incumbents: Rating levels went up, the correlation between ratings and market-implied yields fell, and the ability of ratings to predict default deteriorated. We offer several possible explanations for these findings that are linked to existing theories.     

Is There a Difference Between Solicited and Unsolicited Bank Ratings and, If So, Why?

This paper analyses the effect of soliciting a rating on the actual outcome of bank ratings. Using two sample banks (one rated by Fitch and one rated by S&P), I find evidence that unsolicited ratings tend to be lower than solicited ones, after accounting for differences in observable bank characteristics. This downward bias does not seem to be explained by the fact that better-quality banks self-select into the solicited group. Rather, unsolicited ratings appear to be lower because they are based on public information and are therefore dependent on the quantity of public information disclosed by the banks. As a result, unsolicited ratings tend to be more conservative than solicited ratings, which incorporate both public and non-public information. While the latter result is also consistent with the fact that credit rating agencies may blackmail low-disclosure firms, the findings suggest that blackmailing—if it is actually used—is ineffective in making these firms start to pay for a rating.     

Split bond ratings and rating migration

This paper examines the relationships between split ratings and ratings migration. We find that bonds with split ratings are more likely to have future rating changes. A one-notch (more-than-one-notch) split rating increases the probability of rating change within one year of initial issuance by about 3% (6%). Furthermore, we find that about 30% of split rated bonds have their two ratings converge after four years of initial issuance. The rating convergence tapers off after three years, and the rating agency with a higher (lower) initial rating generally maintains a higher (lower) rating in subsequent years if the two ratings do not converge. We also show that rating transition estimation can be improved by taking into consideration split ratings. We find that one-year rating transition matrices are significantly different between non-letter-split rated bonds and letter-split rated bonds, and we show that the difference has an economically significant impact on the pricing of credit spread options and VaR-based risk management models. Overall, our results suggest that split ratings contain important information about subsequent rating changes.     

Information effect of entry into credit ratings market: The case of insurers' ratings

The paper analyzes the effect of competition between credit rating agencies (CRAs) on the information content of ratings. We show that a monopolistic CRA pools sellers into multiple rating classes and has partial market coverage. This provides an opportunity for market entry. The entrant designs a rating scale distinct from that of the incumbent. It targets higher-than-average companies in each rating grade of the incumbent's rating scale and employs more stringent rating standards. We use Standard and Poor's (S&P) entry into the market for insurance ratings previously covered by a monopolist, A.M. Best, to empirically test the impact of entry on the information content of ratings. The empirical analysis reveals that S&P required higher standards to assign a rating similar to the one assigned by A.M. Best and that higher-than-average quality insurers in each rating category of A.M. Best chose to receive a second rating from S&P.     

私有信息、评级偏差和中国评级机构的市场声誉

考虑到评级机构拥有市场声誉的本质在于其可以通过扭曲评级从而对市场产生影响,本文分两步研究中国发行人付费评级机构的市场声誉:第一步,将信用评级对各种基本面因素进行回归,并以实际评级与回归预测值的差值作为评级偏差的量度。与既有文献相比,本文的重要改进是在基本面因素中引入了发债企业与各评级机构(分支机构)最短距离的均值和方差,这能较好地控制因发债企业私有信息可能造成的选择偏误。第二步,考察评级偏差和机构特征如何影响企业的发债成本。研究表明,中国评级机构作为一个整体具有显著的市场声誉,但各评级机构之间存在很大的差异性。最后,考虑到评级机构与发债企业在选址上可能会有集聚效应,我们基于高铁开通事件进行双重差分检验,研究表明本文结论是稳健的。