Metabolic profile by NMR spect: 79 10*27 combinations possible June 13, 2012, 03:35:01 AM Metabolic profile by NMR spect, 79 228 162 514 264 400 000 000 000 000 combinations possible.Dear colleaguesI\'m very young in the field of metabolomics. We use SIMCA-P+ to calculate with PLS and OPLS the best metabolic profile (NMR-spect) that can distinguish between presence or absence of disease.However searching the best combination within 96 metabolites is a huge manual work. If I calculate the possible combinations with 96 metabolites, 79 228 162 514 264 400 000 000 000 000 combinations are possible.Can somebody help me with a programme that selects the combinations with the best possible sensitivity/spec for presence of disease?Thank youMichiel

Metabolic profile by NMR spect: 79 10*27 combinations possible Reply #1 – December 18, 2012, 08:08:30 AM Hello,I am also having this kind of problem with my QSAR work. I have 37 molecules and nearly 300 descriptors to build a meaningfull QSAR model. According to my searches and reading there are many ways to select right combintaion. For examaple Statistica software has a function to choose variable form a list based on their probablistic possiblities. But some times it does not work. \"Genetic Algorithms\" which combinies variables to select best subset is the best solution. As far as I know older versions of Statistica is capable with it.