Testing the Equality of Two Exponential Population Distributions
The Reliable Computer Co. is considering purchasing CPU chips from one of two different suppliers to use in the production of personal computers. It has two bids from the suppliers, with supplier number one offering the lower bid. Before making a purchase decision, you want to test the durability of the chips, and you ob tain a random sample of 50 chips from each supplier. It is known that both CPUs have operating lives that are exponentially distributed, and you want to test the equality of the expected operating lives of the chips.
a. Define a size .10 GLR test of the equality of the means of the two population distributions, i.e., a test of Ho : 01 = 02 versus Ha: not Ho.
b. The respective sample means of operating lives for the two samples were x1 = 24.23 and x2 = 18.23. Conduct the test of the null hypothesis. Does the test outcome help you decide from which supplier to purchase the chips?
c. How would your test rule change if you wanted to test a one-sided hypothesis concerning the means of the population distributions?
d. Consider using the LM test procedure for this prob lem. What is the test rule? Can you perform the test with the information provided?
e. Consider using the WALD test procedure for this problem. What is the test rule? Can you perform the test with the information provided?