Confidence interval
Learning objectives
- Construct a confidence interval for a parameter, as the statistic plus and minus a margin of error.
- Explain the purpose and use of confidence intervals.
- Construct 95% confidence intervals assuming the point estimate follows a normal distribution.
- Calculate the critical value for a C% confidence interval when the point estimate follows a normal distribution.
- Describe how sample size and confidence level affect the width of a confidence interval.
- Interpret a confidence interval and the confidence level in context.
- Draw conclusions with a specified confidence level about the values of unknown parameters.
- Calculate and interpret the margin of error for a C% confidence interval. Distinguish between margin of error and standard error.