Eight of Penguin Classics' ten nearest neighbors are fellow book publishers, and the two exceptions — a news outlet and a literary blog — sit comfortably inside the same reading-culture orbit. Similarity here measures how closely two entities' audiences resemble each other in composition; scores across the top 10 run from 0.93 to 0.96, a narrow band with no single dominant pull.
Penguin Books leads at 0.96, followed by Viking (0.94), Penguin Press (0.94), and Random House (0.94) — all book publishers, all within a few hundredths of one another. Farrar, Straus & Giroux (0.93) and Alfred A. Knopf (0.93) continue the pattern. The two non-publisher entries, Guardian Books (0.94) and The Millions (0.93), are a books-focused news imprint and a literary blog respectively — adjacent to publishing rather than departures from it. Doubleday (0.93) and Riverhead Books (0.93) round out the set.
The flat shape and tight score range together describe an audience that is deeply embedded in a single, coherent world — literary publishing and its immediate media surround — with no meaningful pull toward any outside cluster.