Question:

Examine the Empirical Rule describing the Normal Curve. Compare how the Empirical Rule and Chebyshev''s Theorem describe area under the curve at two and three standard deviations from the mean.

1) What are the differences and why are there differences?

2) In what areas of your daily lives are normal curves used to describe things?

3) What would you say if your local school scored a z = 0 on the fourth grade reading achievement test?

4) Let''s look at sampling distributions. Why will a sampling distribution yield a better view of the population than a single sample? How might a single sample differ from a sampling distribution?

5) Sampling size is something else that we need to consider. At what point in sampling size can we assume that a normal distribution will be seen? Why is this number considered to be one of statistic''s "magic" numbers?