In addition to “classical” approaches, such as the Gaussian CreditMetrics or Basel II model, recentlythe use of other copulas has been proposed in the area of credit risk for modeling loss distributions,particularly T copulas which lead to fatter tails ceteris paribus. As an amendment to...

The New Basel Capital Accord will allow the determination of banks’ regulatory capital requirementsdue to probabilities of default which are estimated and forecasted from internal ratings.Broadly, two rating philosophies are distinguished: Through the Cycle versus Point inTime Ratings. We...

Among the most crucial input parameters for credit portfolio risk models are the co-movements ofdefault risks. Due to limited empirical evidence about the magnitude of correlations the New BaselCapital Accord sets standard requirements for calculating regulatory capital requirements, e.g. in...

One of the greatest challenges in modeling credit portfolio risk is the issue of correlations between borrowers.Up to now no consistent methodology for identifying correlations exists. In general two approachesare employed: “direct” and “indirect” modeling. While the former specify...

With the New Basle Capital Accord banks’ capital requirements are determined with risk weights based on internaland external ratings and probabilities of default (PD’s). PD’s are mostly estimated from historical defaultrates. In recent working papers the Basle Committee on Banking...

In jüngerer Zeit sind im professionellen Portfoliomanagement zunehmend Faktorenmodelle in den Vordergrund bei der Investment-Analyse gerückt und haben klassische Modelle wie das CAPM mehr und mehr verdrängt. Charakte-ristisch für diese Modelle ist, daß lediglich ein...

Zusammenfassung. In jüngerer Zeit werden in zunehmendem Maße Ansätze der Arbitrage Pricing Theory im praktischen Portfoliomanagement eingesetzt. Eine wichtige Klasse stellen die „fundamentalen Faktoren-Modelle“ dar, bei denen unternehmensspezifische Variablen, wie z.B....

Das wohl bekannteste finanzierungstheoretische Gleichgewichtsmodell, das „Capital-Asset-Pricing-Model” (CAPM) wurde von Sharpe (1964), Lintner (1965) und Mossin (1966) ent-wickelt. Das CAPM, das eine lineare Beziehung zwischen der erwarteten Rendite und dem Risiko eines Wertpapiers...

The global financial crisis has shown that many financial institutions dealing with credit derivatives were exposed to severe unexpected losses. This indicates that systematic influences are decisively underestimated particularly with regard to structured products like securitized tranches of...

Default probabilities (PDs) and correlations play a crucial role in the New Basel Capital Accord. In commercial credit risk models they are an important constituent. Yet, modeling and estimation of PDs and correlations is still under active discussion. We show how the Basel II one factor model...