Briefly describe the shape of each of the four normal plots and state whether the marginal distribution of each series is skewed or symmetric and whether its tails appear normal. If the tails do not...

Briefly describe the shape of each of the four normal plots and state whether the marginal distribution of each series is skewed or symmetric and whether its tails appear normal. If the tails do not appear normal, do they appear heavier or lighter than normal? What conclusions can be made from the Shapiro–Wilk tests? Include the plots with your work.

The next set of R code creates t-plots with 1, 4, 6, 10, 20, and 30 degrees of freedom and all four indices. However, for the remainder of this lab, only the DAX index will be analyzed. Notice how the reference line is created by the abline() function, which adds lines to a plot, and the lm() function, which fits a line to the quantiles. The lm() function is discussed in Chap. 9.

If you are running R from Rstudio, then line 7 should be left as it is. If you are working directly in R, then remove the “#” in this line to open a new window for each plot.