The top 10 neighbors for Mark Goulston form a tight, mixed cluster of Professionals, Tech Personalities, and Authors — a composition that spans three distinct subcategories without any single one dominating to the point of structural separation.

Similarity here measures how closely two entities' audiences resemble each other in composition; scores across the top 10 run from 0.92 down to 0.89, a narrow band consistent with the flat shape. Five of the ten neighbors share Goulston's own subcategory — Professionals — led by Winnie Sun at 0.92, Aaron Lee at 0.91, and Leonard Kim at 0.90, with Cynthia Johnson rounding out the group at 0.89. Three neighbors are Tech Personalities: Sean Gardner at 0.91, Jack Phan at 0.90, and Warren Whitlock at 0.89. The remaining two are Authors: J. D. Landis at 0.91 and Murray Newlands at 0.89. The one outlier by category is The ReidOut, a TV Show at 0.90 — the only Marketing Channel in the top 10, and the only non-Celebrities-and-Influencers entity among them.

The flat shape and narrow score range indicate an audience that overlaps broadly and evenly across professional, tech, and author-adjacent spaces rather than concentrating around any single neighbor type.