PRECISION Subcommand (POWER MEANS RELATED command)

The optional PRECISION subcommand estimates the sample size based on confidence intervals. The subcommand takes effect when POWER is specified, TEST = NONDIRECTIONAL, and SD is specified (ES cannot be specified, otherwise SD is ignored). The keyword is ignored otherwise.

HALFWIDTH = values

The optional keyword specifies the values of the confidence interval half-widths. At least one value must be specified. When multiple values are specified, they are separated by a blank space (or blank spaces). All valid values must be greater than 0. Duplicate values are ignored.