When Thursday Night Football is over, Big Bang and Life in Pieces will be followed by Mom and new comedy Angel From Hell and Elementary. Person of Interest, which did not get a full 22-episode order, will be held for midseason, as are 2 Broke Girls, Mike and Molly and The Odd Couple.
In statistics there are two kinds of means: population mean and sample mean. A population mean is the true mean of the entire population of the data set while a sample mean is the mean of a small sample of the population.
The test statistic will be the sample average $$X=\bar{Y}=\frac{1}{n}\sum_{i=1}^{n}{Y_i},$$ which in each case (Normal, Binomial, Poisson) is a normal random variable; the mean and variance of $X$ depends on the data's distribution.