PASS Confidence Intervals - SD and Variance

PASS 2008 has eight procedures that calculate the sample size necessary to achieve a specified interval width or distance from the variance or SD to the confidence limit at a stated confidence level for a confidence interval about the variance or SD when the underlying data distribution is normal.

These procedures analyze confidence intervals for
    1. One Standard Deviation using Standard Deviation
    2. One Standard Deviation with Tolerance Probability
    3. One Standard Deviation using Relative Error
    4. One Variance using Variance
    5. One Variance with Tolerance Probability
    6. One Variance using Relative Error
    7. Ratio of Two Variances using Variances
    8. Ratio of Two Variances using Relative Error

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PASS 11
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We are pleased to announce the availability of PASS 11. This edition adds over 17 new procedures and features to PASS.

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PASS 11.

"Researchers seeking software to determine sample size have a wide range of choices... Researchers seeking a comprehensive, commercial program for analysis of statistical power and precision should consider PASS 2008."

- Patrick Dattalo
"A Review of Software for Sample Size Determination"
Eval Health Prof, 2009.

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PASS Update

Most Recent Version:
PASS 11
Version 11.0.8
Released December 2, 2011

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