I understand that negative z-score in pathway analysis of differentially expressed genes means stability between conditions. In other words the list of submitted genes contains less than expected genes belonging to that pathway.
I submitted to Enrichr an artificial list of 10 genes belonging to the Hippo signalling pathway (DCHS1, DCHS2, FAT1, FAT2, FAT3, FAT4, WWC1, NF2, MST1, MST2). Under KEGG 2016 analysis, Hippo signalling is the sole one identified but features a negative z-score.
How should this negative score be interpreted?