The Nelder-and-Mead simplex method is employed to obtain optimal sets of parameters (m, n, a) used in the commonly used form of Archic's equation.This derivative-free optimization method avoids trapping by local optima. We have found that the method is very effective, highly efficacsmts, and easily implemented on a PC. The agreement between the results obtained from this method and those from the nonlinear least-squares approach is remarkable. A comparison paper addresses the same problem via fuzzy regression. Authors D. S. Chen is a professor of Industrial Engineering at the University of Afabema, where he has taught linear, integer, end noniirtaar programming since 1970. He reeeived his PhD in Operations Raaearoh from SUNY at Suffalo in 1970. His research interests induda devebpment and application of algorithms for Iarge-seaie optimization modeis. J. H. Fang is a professor of Oeobgy at the University of Aiabama. He received his BS degree from Natienai Taiwan University, and his PhD from Pennayhmnia State University in 19S1. He was orrea a mineralogist, and a mineraf, "Fangite" (~AsS4 ), was named after him. M. E. Kortright is currently in the doctorai program in Computer Science at the University of Afabama, having received his MS and BM degrees front the same inafitutton. His major research area is graph aigofithrna. H. C. Chen b a professor of Computer Sderrca at h University of Alabama. She received a PhD from the State University of New York at Buffaio in 1972, Her research interests irtelude algorithm design, Ai techniques, expert systems, neurai networks, and fuzzy iogic, SPE Adwnccd Technology .%!rics. Vol. 3. No, 1 I Authora I H. C. Chen is a professor of Computer Sdenca at itte University of Alabama. She reeeivad a PhD from the Sfata University of New York at Suffalo in 1972. Her research interesk include algorithm daalgn, Al taehnlquea, expert systems, neural networks, and fuzzy Iogk. J. H. Fang is a professor of Geology at the University of Alabama, He raeefved his S8 * gtee from Natfonal Taiwan University, and his PhfJ horn Pennsylvania Stab University in 1881, He was onos a minertsiogiat,and a mineral, "Fsngite" (Tl#sS4 ), was named after him. M. E. Kortright is ourrentfy in the dootorai program in Computer Sdenea at the University of Ak3banra, having reeeivad his MS and SM degrees from the aanw institution. Hk major research area is graph afgorithma. D. S. Chan is a professor of fnduatriai Engineering at the University of Alabama, where ha has taught iinear, integer, end noniinear programming since 1970, Ha receiwd his PhD in Operations Research from SUNY at Suffafo in 1970. His research interests indude development and application of afgoritims for far~seafe optimizationmodeis, SPE Aclvonccd Tcchrmlogy %xics, Vol. 3, No. 1