This is a simple calculator for conducting a hypothesis test for a single-sample **t-test, sigma not known**. [Note: some authors refer to this as the Small Sample test.]

Enter your data in the blue cells. Change the math operator in the orange box in step 2 to the one in your problem. To get the operator drop-down menu, left-click in the orange cell, e.g. on the current operator. All the yellow cells will automatically update.

Important Note: BUS 233 Requirements for using the t-distribution:

- The population standard deviation, sigma (σ), is
**not**known. - The population is normally distributed or the random sample size is greater than or equal to (>=) 30.

**If sigma is known, use the z-test [here]**. If sigma is not known, use the t-test.

Hope this helps.

Dr. Dawn

Download the Excel workbook V1.03_Single-sample t-test for Mean Sigma Not Known-complete