Question

A constant objective in the manufacture of contact lenses is to improve the level and variation for those features that affect lens power and visual acuity. One such feature involves the tooling from which lenses are ultimately manufactured. The results of two initial process development runs were examined for Critical Feature A. Two distinct product lots were manufactured with slight differences designed to affect the feature in question. Each lot was then sampled and summary results are given below. Lot 1: n1 = 8 X¯ 1 = 0.01525 S1 = 0.00547 Lot 2: n2 = 16 X¯ 2 = 0.02856 S2 = 0.00680 Based on the assumption that the variances between Lot 1 and Lot 2 are equal, is there any evidence of a difference in the MEAN levels of Critical Feature A between Lot 1 and Lot 2. Use α = 0.05. 6. Set up the hypotheses. 7. Calculate the test statistic 8. Identify the distribution of the test statistic. 9. Draw the graph and determine p-value, 10. What is the decision? Write a complete conclusion. 11. Compute a 95% confidence interval for the difference in the mean levels of Critical Feature A between Lot 1 and Lot 2.

Answer 1