The competitive advantage of small American factories such as Tolerance Contract Manufacturing lies in their ability to produce parts with highly narrow requirements, or tolerances, that are typical in the aerospace industry. Consider a product with specifications that call for a maximum variance in the lengths of the parts of 0.0008. Suppose the sample variance for 30 parts turns out to be s2 = 0.0009. Required:
Use α = 0.05 to test whether the population variance specification is being violated. State the null and alternative hypotheses.