Sample Size Determination

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One Sample: Estimation of Mean

This utility can be used to calculate required sample size when your objective is to estimate mean of a qualitative data.

Formula used and other details
Your guesstimate of Standard Deviation Approxiate estimate of Standard Deviation, based on previous studies / pilot studies etc.
Confidence Level %

In percentage. Commonly used values are 95, 99 and 90. Should be between 0.01 to 99.99.
Allowable error
Absolute - Margin of error towards both sides of mean. Relative - Margin of error, equal to this percentage of real mean on its both sides.
Sample Size Required =