Posts: length, engagement and titles

Word count is Substack's own count for every scanned post. Reactions are counted at least days after publication ( human, mixed and AI posts had aged enough when their counts were refreshed). Mixed posts are longer than either extreme, which is partly mechanical: a long post has more room to carry both kinds of text. The reactions chart makes the zero bar's story plain: the share of posts with no reactions at all is the first thing that differs between the groups.

Reactions per thousand subscribers uses the publication's subscriber count as shown on the author's profile, where it is visible.