Locate the basic statistics for your data. A statistics program will output the basic statistics for your data after you have entered the data. The basic statistics include the sum of squares" statistics. You need the sum of squares treatment and sum of squares total statistics. Write these statistics as SSTr and SST.
Calculate the sum of squares error statistic. Call this statistic SSE. The calculation can be computed from SSB and SSTr using the formula SSE = SSTr -- SSB.
Compute the degrees of freedom for the treatment in the analysis. Call it dfTr. Calculate dfTr by the following rule: dfTr equals the number of distinct groups in the analysis minus 1.
Compute the degrees of freedom for the error in the analysis. Call it dfE. Calculate dfE by the following this rule: dfE equals the number of groups in the analysis multiplied by the number of data points in each group -- subtract the number of groups from this final number.
Find the mean square for treatment, MSTr. Use the formula MSTr = SSTr / dfTr.
Find the mean square for error, MSE. Use the formula, MSE = SSE / dfE.
Calculate the F statistic. This statistic is given by F = MSTr/ MSE.
Find the p-value associated with this F statistic. Open your statistics textbook to the F table. Follow the rows and columns until you find the combination of dfTr and dfE from your analysis. Find the F value in the book that is closest to the F value you calculated.