Consider the following plot of quarterly sales data from an Australian online wine retailer: A.Describe the two primary visual features/characteristics that are present in the above plot of the data. Given the nature of the data, why might these features be present? That is, what could be some underlying factors that might be driving the fluctuations that you observe?
B.Suppose that you've been tasked with computing seasonal indices for each quarter. Would you use an additive or multiplicative model to compute these seasonal indices? Why might these seasonal indices be useful to the online wine retailer?
Quarterly Online Sales Volume of Wine from Q4 2007 to Q1 2020
500
450
400 Sales ('000s of Bottles) 350 300
250
2008
2010
2012
2014
2016
2018
2020
Date