Nitric oxide is sometimes given to newborns who experience respiratory failure. In one experiment, nitric oxide was given to 114 infants with respiratory failure. This group was compared to a control group of 121 infants with respiratory failure. The length of hospitalization (in days) was recorded for each of the 235 infants. The mean in the nitric oxide sample was 1 = 36.4; the mean in the control sample was 2 = 29.5. A 95% confidence interval for μ1 - μ2 is (-2.3, 16.1), where is the population mean length of hospitalization for infants who get nitric oxide and μ2 is the mean length of hospitalization for infants in the control population.60
(a) True or false (and say why): We are 95% confident that μ1 is greater than μ2> since most of the confidence interval is greater than zero.
(b) True or false (and say why): We are 95% confident that the difference between μ1 and μ2 is between -2.3 days and 16.1 days.
(c) True or false (and say why): 95% of the nitric oxide infants were hospitalized longer than the mean of the control infants.