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Uncertainty appears to have both a short-run and a long-run component, which we measure using rm and macro implied volatility data from options of 30 days to 10 years duration. We ask what may be driving uncertainty over these di erent time horizons, nding that oil price volatility is particularly important for short-run uncertainty, policy uncertainty is particularly important for long-run unc...

Banks using either the Foundation or Advanced option of the Internal Ratings Based approach to credit risk under Basel II must estimate long-run annual average default probabilities for buckets of homogeneous assets. The one-factor model underlying the capital calculations in Basel II has implications for the distribution of average (across assets) default rates over time. One of these implicat...