An Arizona State University professor, R. Jacobowitz, Ph.D., in consultation with G. Vishteh, M.D., and other neurosurgeons obtained data on operative times, in minutes, for both a dynamic system (Z-plate) and a static system (ALPS plate). They wanted to perform a hypothesis test to decide whether the mean operative time is less with the dynamic system than with the static system.
a. Identify the variable.
b. Identify the two populations.
c. Determine the null and alternative hypotheses.
d. Classify the hypothesis test as two tailed, left tailed, or right tailed.