Document Type : Research Paper

**Authors**

Faculty of Mathematics, Kim Il Sung University, Taesong District, Pyongyang, D. P. R. Korea.

**Abstract**

The aim of this paper is to generalize the comprehensive structural model for defaultable fixed income bonds (considered in R. Agliardi, A comprehensive structural model for defaultable fixed-income bondsو Quant. Finance 11 (2011), no. 5, 749--762.) into a comprehensive unified model of structural and reduced form models. In our model the bond holders receive the deterministic coupon at predetermined coupon dates and the face value (debt) and the coupon at the maturity as well as the effect of government taxes which are paid on the proceeds of an investment in bonds is considered. The expected default event occurs when the equity value is not enough to pay coupon or debt at the coupon dates or maturity and an unexpected default event can occur at any time interval with the probability of given default intensity. We consider the model and pricing formula for equity value and using it calculate expected default barrier. Then we provide pricing model and formula for defaultable corporate bonds with discrete coupons, and consider the duration and the effect of the government taxes.

**Keywords**

**Main Subjects**

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June 2017

Pages 575-599

**Receive Date:**25 August 2014**Revise Date:**01 December 2015**Accept Date:**09 December 2015**First Publish Date:**01 June 2017