Decomposition models are often utilised by official statistical agencies in order to provide an explicit breakdown of time series data into trend, seasonal and irregular components. This paper seeks to explore the volatility in these estimates, incorporating the additional variation contributed...

The Autoregressive Conditionally Heteroscedastic (ARCH) model is useful for handling volatilities in economical time series phenomena that ARIMA models are unable to handle. The ARCH model has been adopted in many applications that contain time series data such as financial market prices,...