Bioassay selection. Based on the definitions of activity cliff from previous studies, specific bioactivity data types including pK i , pK d , pEC 50 , and pIC 50 were selected for comprehensive AC effect estimation. Other assay data types were excluded due to the unreliability of their experimental noise levels in supporting consistent AC analysis. The constructed pK i , pK d , pEC 50 , and pIC 50 benchmark datasets were used for subsequent model training and comparison.