Page 354 - Excel for Scientists and Engineers: Numerical Methods
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CHAPTER 14 NONLINEAR REGRESSION USING THE SOLVER 33 1
The parameters V,,, and K,, can be obtained from the slope and intercept of
the straight line (V,,, = Uintercept, K,, = interceptlslope). However, the
transformation process improperly weights data points during the analysis (very
small values of V result in very large values of 1/V, for example) and leads to
incorrect values for the parameters. In addition, relationships dealing with the
propagation of error must be used to calculate the standard deviations of V,,, and
K,,, from the standard deviations of slope and intercept.
0.00 '
0 5 10
1 /PI
Figure 14-1 1. Double-reciprocal plot of enzyme kinetics.
The curve is calculated using equation 14-10 with V,, = 50, K,,, = 0.5.
By contrast, when the Solver is used the data do not need to be transformed,
ycalc is calculated directly from equation 14-7, the Solver returns the coefficients
V,,, and K,,, and SolvStat returns the standard deviations of V,,, and K,n.
