Discussion:
Eleven percent of the products produced by an industrial process over the past several months fail to conform to specifications. The company modifies the process to reduce the rate of non-conformities. In a trial run, the modified process produces 16 nonconforming items out of a total of 300 produced. Do these results demonstrate that the modification is effective? Support your conclusion with a test of significance. Assume all conditions have been met.
a. Define the parameter and the population of interest for the hypothesis test.
b. State the type of test you will perform.
c. Write the null and alternate hypotheses.
d. What is the test statistic and the p-value of the test?
f. Construct and interpret a 95% confidence interval for the proportion of nonconforming items for the modified process.