A researcher wanted to examine the effectiveness of Vitamin C on the number of colds a year. The researcher obtained a sample of adults and asked to take Vitamin C daily. The average number of colds a year among adults is known to have the average of μ = 3On the basis of this sample, can the researcher conclude that Vitamin C has an effect on the number of colds a year? Use alpha =.05 two-tailed test. Colds: 2,2,2,1,3,3,1,2 Conducta two-tailed test with alpha = .05. Q1: State your null and research hypotheses using complete sentences Q2: What is the df? Q3: What are the cut-off points Q4: What is the standard deviation? You can just include the answer for the mean, SS, and the standard deviation. No need to type your computation. Q5: What is the estimated standard error? Show your computation. Q6: What is the t-value? Show your computation. Q7: State your conclusion thoroughly.

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 + ...