Summary for Week 6 (October 19-21)

We continued our apple juice can example where the content of the cans was uniformly distributed between 950mL and 1050mL. We calculated the probability that a randomly selected can had between 980 and 1020 mL of apple juice by simply finding the area of a rectangle.

In Section 5c, normal distribution was introduced. I illustrated this distribution by using data sets of heights and exam results. We also looked at some web sites describing Galton's board which illustrates the principle that binomial converges to the normal.

This chapter ended with a discussion of probability calculations which became possible by converting the X r.v. to a standardized Z r.v. We also analyzed the reverse problem of calculating the z-values, given the probability.

Chapter 6 is concerned with sampling distributions and the first topic discussed here was the distribution of the sample mean. We started a detailed example of four groups of stocks and compared its probabilistic properties to the properties of the sample mean and its distribution.

We will continue and finish Chapter 6 in Week 7.