Much has been said about airline deregulation and the effects it has had on the airline industry and its performance. Following a deluge of complaints from pas- sengers, the public relations officer of one of the major airlines asked the company's operations manager to look into the problem. The operations manager obtained average takeoff delay ?gures for a random sample of the company's routes over time periods of equal length before and after the deregulation. The data, in minutes of average delay per route, are as follows.
Before: 3, 2, 4, 5, 1, 0, 1, 5, 6, 3, 10, 4, 11, 7
After: 6, 8, 2, 9, 8, 2, 6, 12, 5, 9, 8, 12, 11, 10
Is there evidence in these data that the airline's delays have increased after deregulation?