Ratings models missed essential collateral risk factors
When — if? — the U.S. private-party securitization market fires back up, RMBS deals are going to face a more stringent — realistic? — set of criteria from at least one rating agency; Fitch Ratings on Thursday unveiled a series of enhancements to its U.S. residential mortgage loss model, known as ResiLogic. The latest revisions to the model will impact Fitch’s expected loss assumptions and credit enhancement levels for RMBS, the company said; what’s perhaps most surprising about the update, however, is that it suggests just how rudimentary some of the ratings process really has been. For example, among the changes in ResiLogic 2.0 are the introduction of MSA and national macroeconomic risk multipliers, which will allow the model to fine-tune its estimates... more»