Euclidean? Then nearest neighbor itself is rarely what you want: https://link.springer.com/chapter/10.1007%2F3-540-49257-7_15 https://link.springer.com/chapte

Euclidean? Then nearest neighbor itself is rarely what you want: https://link.springer.com/chapter/10.1007%2F3-540-49257-7_15 https://link.springer.com/chapter/10.1007%2F3-540-49257-7_15. Quote from abstract: "We show that under a broad set of conditions (much broader than independent and identically distributed dimensions), as dimensionality increases, the distance to the nearest data point approaches the distance to the farthest data point" In the end - in the physical world - everything maps to 3D give or take a few dimensions that are very small if we have to believe some physicists. You just have to find the mapping. :-)