A company assembles remote controls for television sets. The company’s design engineers have developed a revised design that they think will make it faster to assemble the controls. To test whether the new design leads to faster assembly, 14 assembly workers were randomly selected and each worker was asked to assemble a control using the current design and then asked to assemble a control using the revised design. The times in seconds to assemble the controls are shown in the file Remote Control. The company’s engineers are unable to assume that the assembly times are normally distributed, but they would like to test whether assembly times are lower using the revised design.
a. What statistical test do you recommend the company use? Why?
b. State the null and alternative hypotheses of interest to the company.
c. At the 0.025 level of significance, is there any evidence to support the engineers’ belief that the revised design reduces assembly time?
d. How might the results of the statistical test be used by the company’s management?