How to Find Margin of Error on MegaStat
- 1). Open Microsoft Excel and click on "MegaStat" on the toobar at the top. Then, click on "Confidence Intervals/Sample Size."
- 2). Choose "Confidence Interval - mean" from the tabs at left.
- 3). Select your desired confidence level from the drop-down (90, 95 or 99 percent). Type in the mean from your statistical data, as well as your standard deviation and sample size (n). Then click "OK." Your confidence interval will appear in the boxes at the bottom, with the lower and upper values. This interval defines your margin of error; anything outside this interval is not a valid result.
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