[coldtea]

>Saying "Near lossless" to mean 90% accurate retrieval of saved vectors is simply a lie. Lossy-ness is binary, not something you can paper over with getting close enough.

Lossy-ness is a binary, "near lossness" however is still valid (and is not the same as saying lossless).

How else, if not by comparing to "lossness" (whether with a more abstract qualitative term like "near" or with some distance or error measurement) do you report the level of fidelity to non-lossy results?

Depends on the context, but even in abstract for whatever domain, 90% sounds pretty close if we're talking about a linear level of degradation corresponding to each X% level.

In this case if this is calculated on a lossless baseline that's itself close to 90% - it's distance from it, it doesn't represent distance from some pure 100% perfect retrieval. So ~90% vs ~89% is very close to lossless capability.