8. Historical Data Set In 1908, “Student” (William Gosset) published the article “The Probable Error of a Mean” (Biometrika, Vol. 6, No. 1). He included the data listed below for two different types of straw seed (regular and kiln dried) that were used on adjacent plots of land. The listed values are the yields of straw in cwt per acre.

a. Using a 0.05 significance level, test the claim that there is no difference between the yields from the two types of seed.

b. Construct a 95% confidence interval estimate of the mean difference between the yields from the two types of seed.

c. Does it appear that either type of seed is better?

x x

Regular 19.25 22.75 23 23 22.5 19.75 24.5 15.5 18 14.25 17 Kiln dried 25 24 24 28 22.5 19.5 22.25 16 17.25 15.75 17.25 Cumulative Review Exercises 509 Cumulative Review Exercises