Market-implied rating
Introduction A '''market-implied rating''' estimates the market observed default probability of an individual, corporation, or even a country. Indeed, a '''credit rating''' is simply a probability of default. The methodology used by Moodys consists in a median piecewise fit of the ratings to the credit defaut swap data observed on the market. S&P however uses a log regression between the log cds and the ratings equivalent number, adjusted to  firm specifics, continent, and outlook.
See also * Alternative data* Credit risk* Default (finance)* Credit history* Credit score* Risk-based pricing
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