Overview (POWER ONEWAY ANOVA command)
POWER ONEWAY ANOVA is an extension of the two sample t-test procedure,
and focuses on the one-way ANOVA and statistical inference about population means for multiple
groups. The procedure estimates the power for two types of hypothesis to compare the multiple group
means, the overall test, and the test with specified contrasts. The over test focuses on the null
hypothesis that all group means are equal. The test with specified contrasts breaks down the overall
ANOVA hypotheses into smaller but more describable and useful pieces of the means.
Options
- Test Assumptions
- Specifies the keywords that control the test assumptions. The settings specify the power values, effect size estimation, group sizes, the pooled population standard deviation, group weights, and the group means.
- Significance Level
- Specifies the significance level of the test's Type I error rate.
- Contrast Test
- Specifies the contrast coefficients and requests the contrast test and determines whether the contrast test is one or two sided.
- Pairwise Differences
- Controls whether or not to estimate the power of testing for the pairwise differences, and determines the adjustment of multiple comparisons.
- Two-Dimensional Plot
- Controls the two-dimensional power by total sample size chart, and the two-dimensional power by pooled standard deviation chart.
- Three-Dimensional Plot
- Controls the three-dimensional power by total sample size (x-axis) and pooled standard deviation (y-axis) chart, and the three-dimensional power by total sample size (y-axis) and pooled standard deviation (x-axis) chart.
- Precision
- Estimates the sample size based on confidence intervals by specifying the values of the confidence interval half-widths.
Basic specification
The basic specification is the POWER ONEWAY ANOVA command and a PARAMETERS subcommand that specifies valid values for the keywords GROUP_MEANS, POOLED_SD, and either POWER or GROUP_SIZES.
Subcommand order
The subcommands can be named in any order.