In a study of the natural variability of rainfall, the rainfall of summer storms was measured by a network of rain gauges in southern Illinois for the years 1960-1964 (Changnon and Huff, in LeCam and Neyman 1967). The following tables give the average amount of rainfall (in inches) from each storm, by year.
a Is the form of the distribution of rainfall per storm skewed or symmetric?
b What is the average rainfall per storm? What is the median rainfall per storm? Explain why these measures differ, using the results of part (a).
c You may have read statements like “10% of the storms account for 90% of the rain:: Construct a graph that shows such a relationship for these data.
d Compare the years using boxplots.
e Which years were wet and which were dry? Are the wet years wet because there were more storms, because individual storms produced more rain, or for both of these reasons?