Relationship between Pol II occupancy and nucleosome occupancy around TSS. (A) Pol II occupancy  around TSS (from -100 to +100) are shown for the four gene classes. Values in each property were normalized, such that their means are zero and standard deviations are one. (B) All genes were divided into five groups according to their average nucleosome occupancy  around TSS (from -100 to +100), and the average Pol II occupancy around TSS was shown for each group. Error bars were calculated by bootstrapping.