- Check the conditions for creating a confidence interval for population proportion.
- Describe the connection between the confidence level and the confidence interval.
- Calculate a confidence interval for a population proportion.
Confidence interval for proportions
Rather than using a simple point estimate, let’s calculate confidence intervals for a population proportion using our statistical tool.
Step 2:
Input the sample size ([latex]n[/latex]) and the number of successes ([latex]x[/latex]).Step 3:
Specify appropriate labels for success/failure by checking the appropriate boxes and typing in labels.Step 4:
Slide the confidence level to the desired level. The default is [latex]95\%[/latex].Step 5: View the [latex]z[/latex] critical value by selecting the box Show [latex]z[/latex]-score for Margin of Error.
Step 6: The confidence interval will appear to the right along with the point estimate, standard error, margin of error, and [latex]z[/latex] critical value (labeled as [latex]z[/latex]-score).