Feedback
We are constantly looking at improving our content, so what could be better than listening to what you as a reader have to say? Your feedback is important to us and we will do our best to incorporate it. Could you take two mins to fill out the feedback form for this book and let us know what your thoughts are about it? Here's the link: https://forms.office.com/r/sYbSyLm2cX.
Thank you in advance.
In Chapter 6, Time Series Analysis and Forecasting, we looked at various approaches to modeling time series. However, models such as ARIMA (Autoregressive Integrated Moving Average) cannot account for volatility that is not constant over time (heteroskedastic). We have already explained that some transformations (such as log or Box-Cox transformations) can be used to adjust for modest changes in volatility, but we would like to go a step further and model it.
In this chapter, we focus on conditional heteroskedasticity, which is a phenomenon caused when an increase in volatility is...