NLP Lineage

Levels

How levels are decided

Each milestone has one of three levels. The level is measured from the documented relationships in the data. Nobody chooses it by hand, and a check rejects any level that does not follow the rule.

The rule

Turning point (25)
At least 4 later milestones build on it directly, were influenced by it, or succeeded it. Its descendants also reach at least 5 of the 10 research threads.
Milestone (131)
At least one later milestone descends from it, but not enough for a turning point. Recent work with no successors yet is also here.
Notable (44)
No later milestone in the data is documented as descending from it, and it is dated before 2025.

Only firm links count: links whose evidence is documented or strong. Weak links (indirect influence, timing only, or a later reading) do not count. Work developed alongside a milestone is not counted as descending from it. These are the same rules as "Before and after" on each milestone page.

What the rule cannot see

The 25 turning points