You are interested in finding a 95% confidence interval for the mean number of visits for physical therapy patients. The data below show the number of visits for 13 randomly selected physical therapy patients. 11,8,12,9,7,12,10,9,8,4,16,9,7, Assume a normal distribution and round your answers to two decimal places. A. The sampling distribution follows a  distribution. B. With 95% confidence, the mean number of visits per physical therapy patient is   between and visits. C. If many groups of 13 randomly selected physical therapy patients are surveyed, then a different confidence interval would be produced from each group. About percent of these confidence intervals will contain the true population mean the number of visits per patient and about percent will not contain the true population mean a number of visits per patient.

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...