QSAR/QSPR Search Algorithms Toolbox

The M-files, an Example and a Toolbox Tutorial is included in the file

In this submission we present the code of the Replacement Method (RM) [1-4] and Enhanced Replacement Method (ERM)[5], that were proposed some time ago by our group. Both methods produce linear regression QSPR-QSAR models that are quite close the FS (full search) ones with much less computational work. These techniques approach the minimum of S by judiciously taking into account the relative errors of the coefficients of the least-squares model given by a set of d descriptors d={X1,X2,…,Xd}. The RM gives models with better statistical parameters than the Forward Stepwise Regression procedure and similar ones to the more elaborated Genetic Algorithms, ERM leads to even better statistical parameters.

1. Duchowicz, P.R., E.A. Castro, F.M. Fernández, and M.P. González, A New Search Algorithm of QSPR/QSAR Theories: Normal Boiling Points of Some Organic Molecules. Chem. Phys. Lett., 2005. 412: p. 376-380.
2. Duchowicz, P.R., E.A. Castro, and F.M. Fernández, Alternative Algorithm for the Search of an Optimal Set of Descriptors in QSAR-QSPR Studies. MATCH Commun. Math. Comput. Chem., 2006. 55: p. 179-192.
3. Duchowicz, P.R.F., M.; Caballero, J.; Castro, E. A.; Fernández, F. M., QSAR of Non-Nucleoside Inhibitors of HIV-1 Reverse Transcriptase. Bioorg. Med. Chem., 2006. 14: p. 5876-5889.
4. Helguera, A.M., P.R. Duchowicz, M.A.C. Pérez, E.A. Castro, M.N.D.S. Cordeiro, and M.P. González, Application of the Replacement Method as Novel Variable Selection Strategy in QSAR. 1. Carcinogenic Potential. Chemometr. Intell. Lab., 2006. 81: p. 180-187.
5. Mercader, A.G., P.R. Duchowicz, F.M. Fernandez, and E.A. Castro, Modified and enhanced replacement method for the selection of molecular descriptors in QSAR and QSPR theories. Chemom. Intell. Lab. Syst. , 2008(in press, doi:10.1016/j.chemolab.2008.02.005).