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Nested Designs - Scholar

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The first way is to use the sums of squares and degrees of freedom computed by SAS to calculate<br />

"by hand" the mean squares and the proper Fs.<br />

The second way is use a TEST statement with PROC ANOVA or with PROC GLM. The TEST<br />

statement syntax is<br />

TEST H=numerator mean square E=denominator mean square;<br />

where "numerator mean square" represents the factor in the model statement whose mean square<br />

goes in the numerator, and where "denominator mean square" represents the factor in the model<br />

statement whose mean square goes in the denominator. Another way to think of it is that "H"<br />

stands for "Hypothesis" and "E" stands for "Error". "H=" signifies the factor about which we<br />

wish to test a hypothesis, and "E=" signifies the factor we wish to use as an error term for the<br />

test.<br />

To test the first two hypotheses mentioned earlier we would use the following TEST statements.<br />

TEST H=HYBRID E=POTS(HYBRID);<br />

TEST H=POTS(HYBRID) E=PLANT(POTS HYBRID);<br />

6. Conclusion<br />

As always, the conclusion is a statement about the alternative hypothesis.<br />

For fixed effects, the hypotheses are about unknown constant parameters, and the conclusion, as<br />

mentioned above, would take the form<br />

or<br />

There is/is not significant statistical evidence that hybrid affects<br />

transpiration rate (P=__ ),<br />

There is/is not significant statistical evidence that mean transpiration rate<br />

differes among hybrids (P=__ ).<br />

nested01.docx 18 4/5/2012

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