[PeterisP]

There's an algorithm to rank the documents by an arbitrary metric. And there's an algorithm to calculate the number of occurrences of each search term in that document.

However, those are insignificant implementation details - all the logic (and all the good and bad results) comes from the arbitrary decision to use the number of occurrences as meaningful for measuring the relevance, from the choice of heuristic.

[Retra]

That's just saying it's the wrong algorithm, not that it isn't an algorithm. Every computation of pi has truncated the result, which is a 'heuristic' decision, but that doesn't invalidate the fact that pi is computed using an algorithm.

All algorithms approximate things, after all. That's simply a consequence of abstraction.