Using the Excel program, enter the data below onto a worksheet. Then touch the Paste Function button on the toolbar. You'll get a menu. On the left side of the menu, select "Statistical." This will make the right side show all the statistical tests you can do with EXCEL. Pick "average" and it will calculate the mean, pick "standard deviation", and it'll do that. You get the idea. Calculate the mean, the variance, and the standard deviation of each of the following sets of numbers:
(a) 4, 0, 1, 4, 3, 6
(b) 5, 3, 1, 3, 4, 2
Which of the sets is more spread out? Draw a histogram of set (a) and one of set (b) to see how the set with the larger variance is more spread out.
Now, suppose that we add 2 to each of the numbers in set (a) above.
That gives us the set that follows: 6, 2, 3, 6, 5, 8
(c) Find the mean and the standard deviation of this set of numbers.
(d) Compare your answers with those for set (a) above. How did adding 2 to each number change the mean? How did it change the standard deviation?
(e) Can you guess, without doing the arithmetic, what will happen to the mean and standard deviation of set (a) from above if we add 10 to each number in that set?
(f) Do the histograms resemble a normal distribution? Explain why or why not.
The solution gives the step by step procedure for the computation of mean, median, standard deviation and histogram.