Modelling the Volatility of GHC_USD Exchange Rate Using Garch Model

Abstract

Modelling and forecasting the exchange rate volatility is a crucial area, as it has implications for many issues in the arena of finance and economics.  Generalised Autoregressive Conditional Heteroskedasticity (GARCH) models with their modifications, is used in capturing the volatility of the exchange rates. Simple rate of returns is employed to model the currency exchange rate volatility of Ghana Cedi-United States Dollar. The daily closing exchange rates were used as the daily observations.  The parameters of these models are estimated using the maximum likelihood method. The results indicate that the volatility of the GHC_USD exchange rate is persistent. The asymmetry terms for TARCH are not statistically significant. Also in TARCH case, the coefficient estimate is negative, suggesting that positive shocks imply a higher next period conditional variance than negative shocks of the same sign. This is the opposite to what would have been expected in the case of the application of a GARCH model to a set of stock returns. But arguably, neither the leverage effect or volatility feedback explanations for asymmetries in the context of stocks apply here.

Keywords: Exchange rate, volatility, GARCH model