Scores

Aggregating means losing — the question is what the new value represents

Mind map of chapter 20: a score is never collected data but a constructed value, presupposing an operator and declared weights. Two species by direction — the score of a criterion, the score of an evaluation — and two profiles. The chapter follows only the column direction: rows are what reveal columns. The operator retained is the discrete upper median, because it stays on the collection scale. No aggregate suffices alone: the minimal pair associates position and dispersion.