Slide 1 Larger is better case (Golf Ball) Linear Model Analysis: SN ratios versus Material, Diameter, Dimples, Thickness Estimated Model Coefficients for SN ratios Term Coef SE Coef T P Constant Material Liquid Diameter Dimples Thicknes Material*Diameter Liquid S = R-Sq = 99.2% R-Sq(adj) = 97.2% Linear Model Analysis and Analysis of Variance (ANOVA)

Slide 2 Analysis of Variance for SN ratios Source DF Seq SS Adj SS Adj MS F P Material Diameter Dimples Thickness Material*Diameter Residual Error Total

Slide 3 Interpreting the results The order of the coefficients by absolute value indicates the relative importance of each factor to the response; the factor with the biggest coefficient has the greatest impact. The sequential and adjusted sums of squares in the analysis of variance table also indicate the relative importance of each factor; the factor with the biggest sum of squares has the greatest impact. These results mirror the factor ranks in the response tables. In this example, you generated results for S/N ratios and means. For S/N ratios, all the factors and the interaction terms are significant at an a-level of For means, core material (p=0.045), core diameter (p=0.024), and the interaction of material with diameter (p=0.06) are significant because their p- values are less than However, because both factors are involved in the interaction, you need to understand the interaction before you can consider the effect of each factor individually.

Slide 4 Source : Minitab Reference Manual