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The enrichment score shown in the enrichment report is the negative natural log of the enrichment p-value derived from Fisher Exact test. The higher the enrichment score, the more overrepresented our list of genes in the gene set of a GO/pathway category.

In KEGG pathway, genes can be colored by Fold change and p-value etc, how are the gene statistics calculated?

During GSEA computation, we also perform ANOVA on each gene based on the attributed selected independent from GESA computation. The results of ANOVA is only used to color the genes in the KEGG gene network. If GSEA is computed using another other database, e.g. GO, we don't compute ANOVA on each gene since GO databased doesn't have gene network information.

When should I use GSEA or Gene set ANOVA?

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