Songlinks › How it decides
How Songlinks decides whether two songwriter records are one person
Two registrations go in. First a gate: do they share any catalogue that counts? Then a chain of questions about the evidence, each answer a push toward “same” or “different”. Many such chains put their pushes on a pair of scales, and the needle settles in one of three zones. Then many pairs at once.
What you just watched
The gate
Songlinks compares records two at a time, but only when they share a publisher, co-writer or administrator that counts (not a society, a major or an aggregator). Without that, no score is computed and nothing is written: a name alone is never evidence. That is most pairs, and it is on purpose: Songlinks abstains rather than guess.
The board is a chain of questions
Each peg asks one thing about the pair: do they share a publisher, do they share co-writers, is the spelling rare, do both carry an IPI name number. The ball’s route is the pair’s answers, and the slot it lands in is a push toward “same” or “different”. That push is the chain’s whole say.
The scales are all the other chains
There are many chains of questions, and every one of them puts a weight on the “same” pan or the “different” pan. The needle is their sum. No single question, and no name match on its own, can move it far.
The zones are the rules
In the green the two records are joined. In the amber nothing is written: a person opens both records and decides. In the grey they stay apart. The bar for joining is high on purpose, because a wrong join pays the wrong person.
The four pairs are made up, names included, to show the four outcomes. The questions are the kinds of evidence Songlinks weighs, in plain words; the pushes are sizes, not scores. What the model is, which questions it asks in what order and where its lines are drawn is not published, as About explains; the FAQ says what kind of model it is.