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Estimation for Single Population

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Chapter 8
Statistical Inference: Estimation for Single Populations

LEARNING OBJECTIVES

The overall learning objective of Chapter 8 is to help you understand estimating parameters of single populations, thereby enabling you to:

1. Know the difference between point and interval estimation.

2. Estimate a population mean from a sample mean when ( is known.

3. Estimate a population mean from a sample mean when ( is unknown.

4. Estimate a population proportion from a sample proportion.

5. Estimate the population variance from a sample variance.

6. Estimate the minimum sample size necessary to achieve given statistical goals.

CHAPTER TEACHING STRATEGY

Chapter 8 is the student's introduction to interval estimation and estimation of sample size. In this chapter, the concept of point estimate is discussed along with the notion that as each sample changes in all likelihood so will the point estimate. From this, the student can see that an interval estimate may be more usable as a one-time proposition than the point estimate. The confidence interval formulas for large sample means and proportions can be presented as mere algebraic manipulations of formulas developed in chapter 7 from the Central Limit Theorem. It is very important that students begin to understand the difference between mean and proportions. Means can be generated by averaging some sort of measurable item such as age, sales, volume, test score, etc. Proportions are computed by counting the number of items containing a characteristic of interest out of the total number of items. Examples might be proportion of people carrying a VISA card, proportion of items that are defective, proportion of market purchasing brand A. In addition, students can begin to see that sometimes single samples

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