Sample Size Calculation, Several Means, Planned Contrast

Sample size calculation for planned contrast with option for charts of power vs. sample size, power vs. standardized effect size and, power vs. alpha level

General

Element Name Description
Power Goal Power goal for the sample size calculation (acceptable range 0.65 to 0.999).
Number of Groups Number of groups in the analysis (acceptable range 2 to 200).
Standardized Effect Standardized effect for use in the model (acceptable range -5000 to 5000).
Alpha Level Alpha level (Type I error rate used in determining the critical value of the t-statistic) (acceptable range 0.0001 to 0.25).
SS Weights Sum of the squares of the contrast weights used in computing the contrast being tested.
Detail of computed results reported Output level of detail selection:

 Sample Size Calculation produces Sample Size Calculation Spreadsheet;

 Smpl Size Calc plus Charts option produces, in addition, Sample Size vs. Standardized Effect chart, Sample Size vs. Alpha Level chart, and Sample Size vs. Power chart.

Chart Parameters

Element Name Description
Number of Steps. (For charts only) Number of individual steps for which to calculate power between the starting and ending parameter values for Sample Size Charts (Min 4, Max 100).
Starting Power. (For charts only) Initial power value for calculation of Sample Size Power vs. Power chart (acceptable range 0.05 to 0.99).
Ending Power. (For charts only) Final power value for calculation of Sample Size chart Vs Power (acceptable range 0.10 to 0.999).
Starting Standardized Effect. (For charts only) Initial standardized effect size for calculation of Sample Size vs. Standardized Effect chart (acceptable range 0.01 to 9).
Ending Standardized Effect. (For charts only) Final standardized effect size for calculation of Sample Size vs. Standardized Effect chart (acceptable range 0.02 to 10).
Starting Alpha Level. (For charts only) Initial alpha level for calculation of Sample Size vs. Alpha Level chart (acceptable range 0.0001 to 0.2499).
Ending Alpha Level. (For charts only) Final alpha level for calculation of Sample Size vs. Alpha Level chart (acceptable range 0.0002 to 0.25).