Mathematical multidimensional spiky spikes
https://gyazo.com/9ffbc15d64803a29d328244ea591a147
This means that in this of [Public Opinion Map 3970 UMAP
https://gyazo.com/30c9d0303e0de3e01269148c72184c1e
Mathematically.
$ N((0, ...) , \sigma) and a small number of $ N((4\sigma, 0, ...) , \sigma) and a small number of data (representation of one spike).
$ 4\sigma means "far enough away".
Since this is tedious, we will write this as 1 (just make $ \sigma that much smaller).
K spikes are (1, 0, 0, 0, ...) , (0, 1, 0, 0, ...) , (0, 0, 1, 0, ...) , ... like this
experiment
SD=0.1
https://gyazo.com/4c4036bfb0383007baa9e66e4a65ce22
SD=0.2
https://gyazo.com/7d9d089ca4db78a451d22fbfb3c762a6
SD=0.3
https://gyazo.com/cd61931f4c4677188428ec8994527616
When it's clearly separated, it's an enclave like UMAP with SD=0.1.
If it's too mixed, you can't tell the boundary, like SD=0.3.
It becomes spiky at its boundaries.
https://gyazo.com/75f8004dc6cbb748f1d0e81d22c24c77
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