These data compare the on-time arrival performance of United and US Airways. The table shows the status of 13,511 arrivals during January 2006. (a) On the basis of this initial summary, find the...

These data compare the on-time arrival performance of United and US Airways. The table shows the status of 13,511 arrivals during January 2006.

(a) On the basis of this initial summary, find the percentages (row or column) that are appropriate for comparing the on-time arrival rates of the two airlines. Which arrives on time more often?

(b) The next two tables organize these same flights by destination. The first also shows arrival time and the second shows airline. Does it appear that a lurking variable might be at work here? How can you tell?

(c) Each cell of the following table shows the number of on-time arrivals for each airline at each destination. Is Destination a lurking factor behind the original
 table?