Match Score

Match Score is a single number from 0 to 100 that summarizes how well two members fit. It's a weighted sum of three components:

1. Personality fit (60% weight) — Big Five facet-vector cosine similarity, with per-facet weights tuned on real friendship outcomes. Some facets count for similarity (Openness, Intellect), some for complementarity (one high and one low on Dominance often beats two highs), some are neutral.

2. Shared interests (25% weight) — Jaccard overlap of interest tags. Capped at 25% so you don't get a 99 score from someone who happens to like the same six things but is wildly incompatible on personality.

3. Proximity (15% weight) — A geographic decay function. 100% within 10 km, 0% above 80 km, smoothly varying in between. Long-distance matches still surface (digital friendship is a real thing) but rank below same-city matches when other signals tie.

A 90+ Match Score is rare and usually corresponds to "this person is shockingly similar to you on the facets that matter for friendship." A 70-80 is solid. Below 60 we usually don't surface at all unless the deck is empty.

The score is symmetric — your Match Score for someone is the same as theirs for you, modulo any tier-specific filtering.