Exercise 8.58 stated that a random sample of 500 measurements on the length of stay in hospitals had sample mean 5.4 days and sample standard deviation 3.1 days. A federal regulatory agency hypothesizes that the average length of stay is in excess of 5 days. Do the data support this hypothesis? Use = .05.

Conditional Probability: probability of an event, given that another event has occurred P(A| B) is the probability of A, given that B has occurred P(A| B) is not the same as P(B|A) If events are independent then P(A)=P(A|B) and P(B)=P(B|A) A contingency table (two way table) is a visual representation of the relationships between the variable. They make probabilities easier to figure out. Levels...