Table 6 Comparison of Models and Operators,,,, Variable,Parameter,Estimate,T,P X1,?1,–1.46,–4.73,0.000 X2,?2,2.84,2.19,0.029 X4,?4,0.18,7.51,0.000 X5,?5,0.014,7.13,0.000 V1X1,?11,2.44,6.04,0.000 V1X2,?12,1.88,1.39,0.166 V2X2,?22,3.52,1.57,0.116 UX4,?1,–0.14,–3.06,0.002 UX5,?2,0.004,0.99,0.325 ANOVA (OPERATOR),,,, Source,Additional SS,df,F,P Operator,131.12,3,13.125,0.000 Error,"2,104.73",632,, Total,"4,964.00",641,, ANOVA (MODEL),,,, Source,Additional SS,df,F,P Model,40.91,2,6.143,0.002 Error,"2,104.73",632,, Total,"4,964.00",641,,