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TABLE  18.5. Comparison of algorithm performance as measured by equivalent function evaluations (efe’s).

                                              Algorithm               19+20      21          21            22            22           23            23           23
                                                                                            With                        With                       With
                                                                                          numerically                numerically                 numerically   Omitting
                                                Type                 Nelder–  Variable   approximated   Conjugate   approximated   Marquardt    approximated   problem
                                                                      Mead     metric      gradient     gradients     gradient                    Jacobian       34†

                                        Code length†                1242       1068                       1059                       1231
                                                                                                                                      2
                                                                     2
                                                                                2
                                        Array elements              n  + 4n + 2  n  + 5n                 5n                          n  + 5n
                                        (a) number of
                                             successful runs        68         68          51            66            52            76            61          75
                                        (b) total efe’s             33394      18292        10797        29158         16065         26419         8021         1 4399
                                        (c) total parameters        230        261          184          236           196           322           255         318
                                        (d) w 1  = (b)/(c)          145·19     70·08       58·68         123·55        81·96         82·05         31·45       45·28
                                        (e) w 0  = average efe’s
                                             per parameter          141·97     76·72       88·25          154·78       78·96         106·01        36·57       67·36
                                                                    0·98       1·09         1·50         1·25          0·96          1·29          1·16         1·49
                                        (f) r = w 0 /W l
                                        (g) a = 1/(2r – 1)          105        0·84        0·50          0·66          1·08          0·63          0·75        0·51
                                        (h) number of failures      6          3           20            5             16            0             8           0
                                        (i) number of problems
                                             not run                5          8            8            8             11            3             10          4
                                        (j) successes as
                                             percentage of
                                             problems run          92         96           72            93            76            100           88           100

                                        † Problem 34 of the set of 79 has been designed to have residuals f so that the second derivatives of these residuals cannot be dropped from
                                        equation ( 17, 15) to make the Gauss–Newton approximation. The failure of the approximation in this case is reflected in the very slow (12000 efe’s)
                                        convergence of algorithm 23.
                                        ‡ On Data General NOVA (23-bit mantissa).
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