> But how did the author get to the rest? I would say: - a recursively iterative process of compressing billions of dimensions down into a very small number

> But how did the author get to the rest? I would say: - a recursively iterative process of compressing billions of dimensions down into a very small number (typically < 5), using mostly predictive heuristics (a highly sophisticated but often incredibly inaccurate process which is typically invisible to the one doing it, and usually observers as well) - aggregation