4.9 Are McDonald's price changes independent?
Refer to the daily price series of McDonald's stock in Exercise 4.8. Instead of looking at the prices themselves, consider now the daily changes in prices found in the provided data file.
mcd
4.9
(a) The price changes over time appear quite random and equally likely to be either positive or negative. (b) There doesn’t appear to be any relationship between the price change and the lag price change. Yes, the series behaves as a series of independent trials because there is no discernable pattern in the plot. (c) Answers will vary.