ST represents the sum of squares. b) SSTr represents the sum of squares. c) SSE represents the sum of squares. d) Which of the following statements is TRUE? SSE = SSTr + SST SST = SSTr - SSE MSE = MSTr + MST MST = MSTr + MSE SST = SSTr + SSE e) Which of the following represents the average between group variation? a. s b. σ c. MSE d. MSTr