The numbers are only estimations. There is no agreement what effect size is small/medium/large">Effect:
Header: You may change groups' name to the real names. Data: When entering data, press Enter after each value. The tool will ignore empty cells or non-numeric cells.
Paste sample data from excel
You may copy the datafrom Excel, Google sheets or any tool that separate data with Tab and Line Feed. Copy one block of 2 consecutive columns includes the header, and paste below. Click to see example: The tool will ignore empty cells or non-numeric cells
F test calculator
Target: To check if the difference between the population's standard deviations of two groups is significance, using sample data The f statistic calculator compute the p-value, the F statistic, and the test power.
H0: σ1≥ = ≤ σ2
H1: σ1< ≠ > σ2
Normal distribution - the F test for variances is very sensitive to the normality assumption.
Required Sample Data
S1, S2 -Sample standard deviations of group1 and group2.
n1, n2 - Sample size of group1 and group2.
The following R code should produce the same results: