Confidence Interval: Mean - One Sample

When entering the confidence level value, the number should be expressed in a decimal format, such as .95.

  • Enter a positive whole number for the sample size n.
  • Enter the value of the sample mean.
  • Enter a positive value of the SAMPLE standard deviation s.
Enter a value for the Population Standard Deviation only if it is known (otherwise, leave it blank). (Entering the value of the SAMPLE standard deviation in the box for the POPULATION standard deviation causes the calculations to be based on the normal distribution, and the results will be affected.)

Click on the Evaluate button to obtain the results.

If the population standard deviation is not known, the confidence interval will be based on calculations using the t distribution. If the population standard deviation is known, the confidence interval will be based on calculations using the normal distribution.

Click on the Print button to print the results.

To close the window, click on the X at the top of the module window.