Residuals pivot value

From this plot, the value at x = 7 appears to be the residual pivot value, wherereas the slopes of e,s go from negative to positive. To get a better view, let us standardize the residuals by... 

Parameter estimation to fit the data is carried out with VARY YM Y1 Y2, FIT M, and OPTIMIZE. The result is optimized values for Ym (0.7835), Y1 (0.6346), and Y2 (1.1770). The statistical summary shows that the residual sum of squares decreases from 0.494 to 0.294 with the parameter optimization compared to that with starting values (Ym=Yl=Y2=l. 0. ) The values of after optimization of Ym, Yl, and Y2 are shown in Figure 2, which illustrates the anchor-pivot method and forced linearization with optimization of the initiator parameters through Yl and Y2. 

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