Advances in Risk Management

(Michael S) #1
JEAN-DAVID FERMANIAN AND MOHAMMED SBAI 145

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Figure 7.5Combined effect of the parametersα 0 andαin the multi-factor
intensity model
We lead many simulations with different values of the parametersα 0
andαiin order to study their combined effects on the loss distribution (see
Figure 7.5).
The variance ofZ 0 +Zivaries from 0.005 to 50 when (α 0 ,α) varies from
0.01 to 100, which seems to be reasonable. The levels of our dependence
indicators seem to be in line with those obtained in section 7.3. Note that we
lose some dependence when the relative importance betweenZ 0 andZiis
balanced. This is due to a diversification effect inside both components of the
frailty factors. Globally, adding an idiosyncratic frailty allow more flexibility
in the model, without losing the ability to reach realistic dependence levels.

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