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.
Each has the same distribution with the same unknown parameter(s) like [math]\lambda[/math], [math]p[/math], [math]\mu[/math], [math]\sigma[/math], [math]k[/math] etc. A statistic is a function of the random sample that may be useful in estimating a parameter. An example of a statistic is the sample mean [math]\overline X=\frac1n(X_1+\cdots+X_n)[/math]. The word statistic is also used for a function of actual data. After performing an experiment, you collect actual data, [math]\mathbf x=(x_1,\ldots,x_n)[/math]. Those are [math]n[/math] numbers which are the outcomes of [math]n[/math] trials.