Power Analysis of One-way ANOVA: Contrast
The Contrast dialog provides options for specifying contrast, coefficient, effect size, pairwise differences, and confidence interval half-width settings for the Power Analysis of One-way ANOVA analysis.
- Contrast Test
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- Test with linear contrasts
- When enabled, the contrast and coefficient settings are available.
- Test direction
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- Nondirectional (two-sided) analysis
- When selected, a two-sided test is used. This is the default setting.
- Directional (one-sided) analysis
- When selected, power is computed for a one-sided test.
- Coefficients
- Use the table to specify the contrast coefficients and request the contrast test. The table values are optional. The number of specified values must be equal to the values specified for Group sizes and Group means. The sum for all specified values must equal 0, otherwise the last value will automatically be adjusted.
- Effect size
- Specify the effect size of the contrast test that is measured by δ. You must specify a single numeric value. When the Test Direction is set to Directional (one-sided) analysis, the specified value must be ≥ 0. When Power is specified as the Estimate test assumption, the specified value cannot be 0.
- Pairwise Differences
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- Estimate the power of testing for pairwise differences
- Controls whether or not to estimate the power of testing for the pairwise differences. Be
default, the optional setting is disabled, which suppresses output for the pairwise differences.
- Bonferroni correction
- Uses the Bonferroni correction in estimating the power of pairwise differences. This is the default setting.
- Sidak correction
- Uses the Sidak correction in estimating the power of pairwise differences.
- Least significant difference (LSD)
- Uses the LSD correction in estimating the power of pairwise differences.
- Specify the half-width of confidence interval
- Estimates the sample size based on the confidence
interval half-width value. Enter a value in the range 0 - 1. For the One-Sample Binomial test, the
value must be in the range 0 - 0.5.Note: Duplicate values are ignored.
- Click Add to add the specified half-width value to the list.
- Highlight an existing half-width value and click Change to update the value.
- Highlight an existing half-width value and click Remove to remove the value from the list.