Overview (POWER MEANS INDEPENDENT command)
POWER MEANS INDEPENDENT invokes power means analysis for the independent sample
t-test.
Options
- Test Assumptions
- Specifies the keywords that control the test assumptions. The keywords specify the sample size, population standard deviation, the population mean under testing, and the effect size. For more information, see PARAMETERS Subcommand (POWER MEANS INDEPENDENT command).
- Significance Level
- Specifies the significance level of the test's Type I error rate.
- Test Direction
- Determines whether the test is one or two-sided.
- Two-Dimensional Plot
- Controls the two-dimensional power by sample size ratio chart, and the two-dimensional power by effect size (or mean difference) chart.
- Three-Dimensional Plot
- Controls the three-dimensional power by sample size (x-axis) and effect size (y-axis) chart, and the three-dimensional power by sample size (y-axis) and effect size (x-axis) chart. Also controls the vertical rotation degrees (clockwise from the left) and the horizontal rotation degrees (clockwise from the front) for the three-dimensional 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 MEANS INDEPENDENT command and a PARAMETERS subcommand that specifies valid values for the keywords MEAN, SD, and either POWER or N.
Subcommand order
The subcommands can be named in any order.