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DIFFERENCE OF MEANS CONFIDENCE INTERVALName:
where
s1 = standard deviation of sample 1 s2 = standard deviation of sample 2 df = the degrees of freedom
=
<SUBSET/EXCEPT/FOR qualification> where <y1> is the first response variable, <y2> is the second response variable, and where the <SUBSET/EXCEPT/FOR qualification> is optional.
DIFFERENCE OF MEANS CONFIDENCE INTERVAL Y1 Y2 SUBSET TAG > 2 DIFFERENCE OF MEANS CONFIDENCE INTERVAL Y1 Y2 SUBSET Y1 > 0
SKIP 25 READ AUTO83B.DAT Y1 Y2 RETAIN Y2 SUBSET Y2 >= 0 SET WRITE DECIMALS 5 DIFFERENCE OF MEANS CONFIDENCE INTERVAL Y1 Y2Dataplot generates the following output: Confidence Limits for the Difference Between Means (Two-Sided) Response Variable 1: Y1 Response Variable 2: Y2 Summary Statistics for Variable 1: Number of Observations: 249 Sample Mean: 20.1446 Sample Standard Deviation: 6.4147 Summary Statistics for Variable 2: Number of Observations: 79 Sample Mean: 30.4810 Sample Standard Deviation: 6.1077 Difference Between Sample Means: -10.3364 Standard Error: 0.7984 ----------------------------------------------------------------- Confidence t t-Value X Lower Upper Value (%) Value StdErr Limit Limit ----------------------------------------------------------------- 50.000 0.676 0.5400 -10.8764 -9.7965 75.000 1.155 0.9224 -11.2588 -9.4141 90.000 1.656 1.3222 -11.6586 -9.0142 95.000 1.977 1.5788 -11.9152 -8.7576 99.000 2.612 2.0856 -12.4220 -8.2508 99.900 3.363 2.6850 -13.0215 -7.6514 99.990 4.008 3.2002 -13.5366 -7.1362 99.999 4.588 3.6632 -13.9996 -6.6733 | |||||||||||||
Date created: 02/25/2003 Last updated: 12/11/2023 Please email comments on this WWW page to alan.heckert@nist.gov. |