Manufacturing and Product Development
The pressure for brewing espresso is necessary to help form cream and to distinguish this drink from strong drip coffee. Random samples of espressos from each of two commercial machines were obtained, and the pressure (in atmospheres) while brewing each cup was recorded. Assume the underlying distributions are continuous. Is there any evidence to suggest that the espresso setting on each machine produces a different median pressure? Use the Wilcoxon rank-sum test with a = 0.05, and find the p value associated with this test.