Chapter 9: Confidence Intervals

Inferential Statistics objective

Estimate

Confidence Interval

Assumptions with Confidence Intervals for Population Mean

(when population standard deviation is known)

Interpretation of Confidence Intervals for Population Mean

(when population standard deviation is known)

Confidence Interval for Population Mean Example (1)

**population standard deviation KNOWN**

Obtaining precise interval for High Confidence

Choosing a sample size

Choosing a sample size Example

Student's t distribution

Student's t distribution (cont.)

Confidence Interval for Population Mean

**when population standard deviation is UNKNOWN**

Confidence Interval for Population Mean Example (1)

**when population standard deviation is UNKNOWN**

Confidence Interval for Population Proportion (pi)

Confidence Interval for Population Proportion (pi) Example (1)

Confidence Interval for Population Proportion (pi) Example (1) (cont.)

Choosing the Sample Size

Confidence Interval for Population Proportion (pi)

Choosing the Sample Size

Confidence Interval for Population Proportion (pi) Example (2)