NB PC12 PC12+NGF C6 A B C D E F G H I J K L Residual Normality Observed Residuals Observed Residuals Observed Residuals Observed Residuals r A2 p = 0.9370 1.4524 0.0008 r A2 p = 0.9476 1.6155 0.0003 r A2 p = 0.8153 2.3826 2.61×10−6 r A2 p = 0.9693 0.9522 0.0141 Expected Normal Values Expected Normal Values Expected Normal Values Expected Normal Values E F G H Linearity Plot Box–Cox λ=0.225 λ=−0.002 λ=0.372 Correlation Coefficient Correlation Coefficient Correlation Coefficient Correlation Coefficient λ=−0.241 Value of λ Value of λ Value of λ Value of λ I J K L Transformed Resid. Norm. Resid. of Transformed Data Resid. of Transformed Data Resid. of Transformed Data Resid. of Transformed Data r A2 p = 0.9778 0.5998 0.1099 r A2 p = 0.9883 0.3352 0.4892 r A2 p = 0.9709 0.3352 0.4892 r A2 p = 0.9971 0.1026 0.9949 Expected Normal Values Expected Normal Values Expected Normal Values Expected Normal Values Supplementary Figure. Normalization of MAPT–CAT fusion clone transfection expression data. MAPT–CAT reporter gene fusion clones were transfected into three different cell lines, specifically NB human neuroblastoma, PC12 rat pheochromocytoma, PC12 cells treated with NGF, and C6 rat glioma cells. CAT ELISA results for transfected cell extracts were adjusted for β–GAL ELISA signals and total protein (Bradford assay). Average adjusted results for each clone within each cell line/treatment, NB (A, E, I), PC12 (B, F, J), PC12 + NGF (C, G, K), and C6 (D, H, L), was subtracted from each appropriate individual adjusted data point. Data was then plotted on a normal probability plot (A–D). Anderson–Darling test showed significant non–normality for all cell lines. Box–Cox transformation: (yλ-1)/λ or ln(y) if λ = 0, was applied to data within each experiment for −3 ≤ λ ≤ 3, at intervals of 0.001. The λ that produced the highest correlation coefficient between residual values and a normal distribution (E–H) was chosen and transformed data was tested by Anderson–Darling for normality (I–L). All results could be transformed to produce normal residuals and were then amenable to analysis.