Node Degree Correlations in Evolved and Natural PDUG

<div><p>(A) Shown is the Z score for the probability <i>P</i>(<i>k</i><sub>1</sub>,<i>k</i><sub>2</sub>) of the two nodes with degree <i>k<sub>1</sub>,k<sub>2</sub></i> being connected to each other in the natural PDUG. Unlike in other networks, nodes of similar degree tend to be connected.</p><p>(B) The Z score plot of <i>P</i>(<i>k</i><sub>1</sub>,<i>k</i><sub>2</sub>) for the structure similarity graph obtained in the evolution model is remarkably similar to the actual one.</p></div>