Answer
- (1) nneighbors: local vs global (5-15 local, 50-100 global; default 15).
- (2) mindist: minimum spacing in embedding — small (0.1) preserves clusters, large (0.5) spreads points.
- (3) ncomponents: usually 2 for viz, 10-50 for downstream.
- (4) metric: euclidean, cosine, correlation, hamming, custom callable.
- (5) randomstate for reproducibility.
- Tune nneighbors+mindist together; try 3-4 combinations.
Check yourself — multiple choice
- No parameters
- nneighbors (local/global), mindist (cluster spacing), ncomponents, metric; try 3-4 (nneighbors,mindist) combos
- Same as t-SNE
- Random
UMAP: nneighbors, mindist, ncomponents, metric; tune first two.
#dimensionality-reduction#visualization
Practise Unsupervised Learning
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