Left Tailed Right Tailed Two tailed . Reject H o. Reject H o. Reject H o Accept H o. Accept H o Reject H o. Accept H o. http://library.beau.org/gutenberg/1/0/9/6/10962/10962-h/images/069.png.
Left Tailed Right Tailed Two tailed
Reject Ho Accept Ho
Accept Ho Reject Ho
New method reduces variances in product
1.41<1.5; How small is enough?
Suppose Hois true (σ²= 1.5), how likely is it to observe S²≤1.41 ?
Chi-sq. with n-1 D.F.
There’s good chance of observing 1.41 in a random sample, even if the true population variance is 1.5.
No reason to reject Ho: No significant evidence of reduced variance.
Variance unequal in two populations
F dist. with 15 and 24 D.F.
Reject Ho at α=0.2: Variances are not equal.
Rank sum W=212
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