_PROBLEM CoEPrA-2006_Classification_002 _GROUP_NAME Scott Oloff _GROUP_MEMBERS Scott Oloff _ADDRESS Boehringer Ingelheim 900 Ridgebury Rd. Ridgefield, CT 06877 _MODELING_PROCEDURE I used a newly developed machine learning approach called kScore, which is based on kNN and SVM technologies. The approach is kernel free and uses all training compounds in a distance-weighted manner to predict a test compound rather than just its k Nearest Neighbors. The algorithm also incorporates Generalization constraints, a soft margin classifier (for Classification), and an Epsilon Loss function (for Regression) similar to those proposed by V. Vapnik. There is a built in Applicability Domain for each kScore model and a more detailed explanation of the method is being submitted for publication. The descriptors of the original training set were normalized from 0 to 1. The training set was then randomly divided into 5 training and test sets whereby the test set contained 20% of the compounds. For each training/test split several kScore models were generated (using the COEPRA provided descriptors) to find the best values of C and Epsilon for external prediction. The most predictive models were collected and used in a consensus fashion to predict the external test set. The average LOO Training accuracies were 0.8-1.0 and the average Test accuracies for each class varied between 0.8 and 1.0. The most predictive values of Epsilon and C varied from 0.8 to 1.2 and 100 to 400, respectively. The descriptor weights of the most predictive model are attached. There were 4 objects that fell just outside of the models' applicability domain. If the predictions are absolutely necessary for comparison in the competition the predictions are: Obj_00015 -1 Obj_00022 1 Obj_00033 -1 Obj_00036 1 _PREDICTION Obj_00001 +1 Obj_00002 +1 Obj_00003 -1 Obj_00004 +1 Obj_00005 +1 Obj_00006 -1 Obj_00007 +1 Obj_00008 -1 Obj_00009 +1 Obj_00010 -1 Obj_00011 -1 Obj_00012 +1 Obj_00013 +1 Obj_00014 +1 Obj_00015 -1 Obj_00016 -1 Obj_00017 +1 Obj_00018 -1 Obj_00019 +1 Obj_00020 -1 Obj_00021 -1 Obj_00022 +1 Obj_00023 -1 Obj_00024 -1 Obj_00025 -1 Obj_00026 -1 Obj_00027 +1 Obj_00028 +1 Obj_00029 -1 Obj_00030 +1 Obj_00031 -1 Obj_00032 +1 Obj_00033 -1 Obj_00034 -1 Obj_00035 -1 Obj_00036 +1 Obj_00037 -1 Obj_00038 -1 Obj_00039 +1 Obj_00040 +1 Obj_00041 -1 Obj_00042 -1 Obj_00043 -1 Obj_00044 -1 Obj_00045 +1 Obj_00046 -1 Obj_00047 -1 Obj_00048 +1 Obj_00049 +1 Obj_00050 -1 Obj_00051 +1 Obj_00052 +1 Obj_00053 +1 Obj_00054 +1 Obj_00055 +1 Obj_00056 -1 Obj_00057 -1 Obj_00058 +1 Obj_00059 -1 Obj_00060 +1 Obj_00061 -1 Obj_00062 +1 Obj_00063 +1 Obj_00064 +1 Obj_00065 -1 Obj_00066 +1 Obj_00067 -1 Obj_00068 +1 Obj_00069 -1 Obj_00070 +1 Obj_00071 -1 Obj_00072 +1 Obj_00073 +1 Obj_00074 +1 Obj_00075 +1 Obj_00076 -1