Estimate the Population Mean from Summary Statistics

How To... > Work with Statistical Objects > Estimate Parameters and Compute Confidence Intervals > Estimate the Population Mean from Summary Statistics

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For numeric data, you need only three numbers, count, mean, and standard deviation, to compute a confidence interval for a mean. If you have these three numbers, you can type them directly into the estimate mean object.

1.	Create a new estimate by dragging one from the shelf or choosing Object \| New \| Interval Estimate.

2.	From the pop-up menu in the estimate’s upper-right corner, choose Estimate Mean.

3.	Double-click the bold, blue field AttributeName in the body of the estimate, and type a reasonable name.

4.	Press Tab to move to the next field and continue inputting appropriate values.

As you enter values, the text changes throughout the estimate object.

This estimate shows a computation of the confidence interval for a sample of 9 scores with a mean of 120 and a standard deviation of 15. Notice that because the estimate is in verbose mode, it describes in detail the meaning of a confidence interval.