Next, the docked compounds are re-scored and re-ranked using the PCscore scoring functions as mentioned above. The enrichment rates are also determined by noting the numbers of active compounds retrieved in the top 1% of the ranked database (Table 5) . When comparing the enrichment rates from PC1score to the results obtained from a single scoring function or conventional consensus scoring functions, PC1score exhibited better performance for the enrichment rates regardless of the scoring function employed to extract the compound pose. For example, PC1score yields 26 active compounds in the Surflex_Score and PMF_Score pose group, which outperforms both the single scoring function with 20 or less active compounds and the consensus scoring method with 24 active compounds. As indicated in Table 5 , application of PC1score results in more active compounds than the application of PC2score and PC3score for each of the five pose group due to the descriptiveness of the first principal component, which shares the maximum amount of the whole variance followed by the decreasing descriptiveness of the other PCs. We did not obtain any active compounds in the top 1% of the ranked database using PC3score because the values of the eigenvalue of PC3 were ,1.