Filtered Historical Simulation for Initial Margin of Interest Rate Swap Under Korean Market

Abstract

We discuss how to determine the margin of interest rate portfolio under Korean interest rate market when the trades are cleared through a clearing house. The analysis is based on the filtered historical simulation using the EWMA and GARCH model for the interest rate process. Due to the irregular feature in the short tenor rates, we observe the instabilities of the filtered processes by the EWMA model, and we propose how to mitigate the instability. We also explain the properties of the inferred volatility processes depending on the volatility model, the observation interval of the interest rate series, and the parameter choice.