Sigorta Sektörünün Kredi Portföy Risk Modeli İle Değerlendirilmesi
Özet
The credit risk, which emerges as a concept of default risk, can be defined as the risk that
any liability of the borrower can not be fulfilled. Default cases arise out of the situations of
delayed payments, the presence of non-payment periods or bankruptcy. The existence of
default cases pose a considerable risk to the lender. For this reason, the lender must carry
out risk management in order to protect himself. In the event of possible default, the lender
should compute the loss and determine the economic capital accordingly.
Economic capital gives the amount between expected and unexpected loss. While it is easy
to calculate the expected loss, it is difficult to calculate the unexpected loss. Therefore,
credit risk models have been developed and a resource has been created for financial
institutions. Sometimes financial institutions use these available methods and sometimes
produce their own internal models.
While credit risk was measured only on credit basis in previous periods; it is now mostly
measured on portfolio basis in the new period. In the portfolio-based measures, taking into
account the relationship of borrowers with each other, a general portfolio loss distribution
is found, so that amount of economic capital, that should be allocated for risk purposes, can be computed more accurately. In portfolio-based credit risk models, default probabilities,
transition matrices, correlations and recovery rates are used depending on model selection.
In addition, the portfolio manager can determine, depending on the risk contributions of
the borrowers, the continuity of borrowers in the portfolio. When it is needed, the portfolio
manager can diversify the portfolio and also play with the amount of concentration.
Portfolio-based credit risk models used in the literature are CreditRisk+ model with an
actuarial approach, CreditPortfolioView model with a macroeconomic approach and
CreditMetrics and KMV models based on asset value. These models show similarities and
differences in some respects. In this study, information about models is given, and
potential similarities and differences are also mentioned. In addition, we conduct a
numerical study in Turkey related to the companies which are investigating non-life
insurance, with the data provided by the Insurance Association of Turkey. In the study, a
portfolio consisting of companies was considered and a portfolio risk analysis was made.
Bankruptcy probabilities of companies are estimated and simulations are created based on
these probabilities. For the analysis, the simulation technique with the logic of the
CreditMetrics method is used and the CreditRisk+ method is applied together with this
technique. Thus, the loss distribution of the insurance sector is obtained. In addition, both
the risk contributions of companies to the insurance sector and the amount of capital
required to hold them in their hands have been determined. Thus, a general observation has
been made about the insurance sector and the state of the sector has been learned in
accordance with assumptions.