What's in Your Wallet? Perhaps due to the increase in use of debit and credit cards, only 20% of Americans always carry cash.30 A sample of shoppers at the Quaker Bridge Mall in Lawrence, New Jersey was obtained and asked if they were carrying cash. The sequence of responses is given in the following table [cash (C) and no cash (N)].
Is there any evidence to suggest that the order of observations is not random? Use the runs test with a ≈ 0.05.