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Using JMP - SAS

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424 Formula Functions Reference Appendix B<br />

Probability Functions<br />

Tukey HSD Quantile<br />

Accepts a probability argument 1-alpha, and returns the 1-alphath quantile from Tukey’s HSD test for the<br />

parameters that you specify. The alpha argument is the significance level that you want. nGroups is the<br />

number of groups in a study. dfe is the error degrees of freedom (based on the total study sample). This is the<br />

quantile used to calculate least significant difference in Tukey’s multiple comparisons test.<br />

Tukey HSD P Quantile<br />

Returns the p-value from Tukey's HSD multiple comparisons test.<br />

F Power and F Sample Size<br />

The F Power function calculates the power from a given situation that involves an F-test or t-test, and the F<br />

Sample Size function computes the sample size. The arguments are the values that you specify for<br />

computation of a prospective power analysis. (These functions perform the same computations as if you<br />

selected DOE > Sample Size and Power. See the Design of Experiments for a discussion of power and<br />

sample size.) The arguments include:<br />

• alpha The significance level that you are willing to tolerate (often 0.05).<br />

• dfh The hypothesis degrees of freedom. It is one (1) for a t-test.<br />

• dfm The model degrees of freedom (such that dfe = n – dfm).<br />

• SquaredSize The squared effect size scaled by the error variance, which is used for making the<br />

noncentrality argument for the F-distribution. For this argument, use squared size = Δ 2 /σ 2 where σ 2 is<br />

the error variance. That is, use:<br />

Δ 2 = ( x – μ) 2 for a one-sample t-test<br />

Δ 2 ( x 1 – x 2 ) 2<br />

= ----------------------<br />

4<br />

for a two-sample t-test<br />

Δ 2 k ( x i – x) 2<br />

= -------------------<br />

k<br />

i = 1 for a k-sample F-test<br />

• n (found only in the F Power function) The total number of observations (runs, experimental units,<br />

or samples) you expect to have. Power (in the F Sample Size function) is the probability that you want<br />

to have of declaring a significant result.

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