The new Basel Accord : implications of the co-existence between the standardized approach and the internal ratings-based approach

We examine the prudential implications of the co-existence between the standardized approach and the internal ratings-based (IRB) approach, as defined in the new Basle Accord. We consider a model in which sophisticated banks, eligible for the IRB approach, and unsophisticated banks, eligible for the standardized approach, allocate their loan portfolio between high-risk and lowrisk borrowers. We find that the co-existence between the two regimes may induce sophisticated banks to decrease risk-taking, but encourage unsophisticated banks to increase risk-taking. The risk reallocation effects are stronger when competition is more intense.