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A fallacy in regression
   Finds the parameters of a certain function or its logarithmised form (with varied results).
 
n, nv, m, itransform 0   1 No. of points, no. of independent variables, no. of parameters, "transform" data. •
X X-values given in "nv" rows. •
Y Y-values. •
krit 1 2 (min. sq.) 3 4 ∞ (minmax) Criterion [power of (ycalcy)].
tol, maxcal Tolerance, max. no. of iterations. •
P Parameters (of order unit). •
Z Scale factors. True values are P.Z.
   Solves a regression for the function below (left-hand equation) or its transformation into a logarithmised, linearised form (right-hand equation).  The values of K and a differ, mainly for the former (about 10 % with the data proposed).  (The values would be identical if the data were "perfect".)  The original form is the legitimate one, although the linearised version is commonly preferred.
func   funcLin
References:
• Hanna, Owen T., Orville C. Sandall, 1995, "Computational Methods in Chemical Engineering", Prentice Hall PTR, Upper Saddle River (NJ), USA, p 148.
 
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Created: 18-Feb-2004 — Last update: 19-Feb-2004