After receiving your report, Tony Scapelli decided to delay the 29-minute guarantee program until after collecting additional data based on your recommendations. Tony also decided to hire two additional drivers for Friday and Saturday deliveries. Over a period of five weeks, Tony monitored deliveries and collected data on the same variables as in his first data collection. To avoid the sampling bias of the earlier data, Tony sampled every 10th pizza delivery order. He carefully measured the time required to prepare the order and the amount of time it had to wait for a driver to become available.
Instead of going on the delivery to measure the travel time, Tony phoned ahead to the waiting customer and offered a discount coupon if the customer would call back with the exact time the pizza arrived. In this way, Tony hoped to avoid the potential for response bias with the delivery person. At the end of the five-week period, Tony had collected the data on 324 deliveries. Assignment: Once again, Tony is relying on you to provide an analysis of the new data that he has collected and to recommend whether or not he should offer the 29-minute guarantee on Pronto Pizza deliveries.
He is committed to going with the 29-minute delivery guarantee unless the data strongly indicate that the percentage of free pizzas given away due to late deliveries exceeds the 5% break-even point. Thoroughly analyze the new data collected by Tony contained in the file ProntoRevisited. Write a statistical consulting report detailing your analysis and your recommendation on the 29-minute guarantee. Be sure to discuss any other innovative things that Tony might do in order to improve his pizza delivery process and compete with his new rival.