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8: Confidence Intervals

Last updated

Feb 19, 2024
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- 7.12: Solutions
- 8.1: Introduction

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In this chapter, you will learn to construct and interpret confidence intervals. You will also learn a new distribution, the Student's-t, and how it is used with these intervals. Throughout the chapter, it is important to keep in mind that the confidence interval is a random variable. It is the population parameter that is fixed.

8.1: Introduction
In this chapter, you will learn to construct and interpret confidence intervals. You will also learn a new distribution, the Student's-t, and how it is used with these intervals. Throughout the chapter, it is important to keep in mind that the confidence interval is a random variable. It is the population parameter that is fixed.
8.2: A Confidence Interval When the Population Standard Deviation Is Known or Large Sample Size
A confidence interval for a population mean with a known standard deviation is based on the fact that the sample means follow an approximately normal distribution.
8.3: A Confidence Interval When the Population Standard Deviation Is Unknown and Small Sample Case
We rarely know the population standard deviation. In the past, when the sample size was large, this did not present a problem to statisticians. They used the sample standard deviation ss as an estimate for σσ and proceeded as before to calculate a confidence interval with close enough results. However, statisticians ran into problems when the sample size was small. A small sample size caused inaccuracies in the confidence interval.
8.4: A Confidence Interval for A Population Proportion
The procedure to find the confidence interval, the sample size, the error bound, and the confidence level for a proportion is similar to that for the population mean, but the formulas are different.
8.5: Calculating the Sample Size n- Continuous and Binary Random Variables
8.6: Key Terms
8.7: Chapter Review
8.8: Formula Review
8.9: Practice
8.10: Homework
8.11: References
8.12: Solutions

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