OPTICS — what does it produce and how do you use it?
hardAnswer
- Computes a reachability plot ordering all points by density-reachability.
- Reveals cluster hierarchy visually as valleys in the plot.
- Extract clusters at any density threshold from a single run.
- Slower than DBSCAN (O(n log n) with index) but more flexible.
- Used as an exploratory tool when you don't know cluster densities in advance.
Check yourself — multiple choice
- Same as DBSCAN
- Reachability plot ordering; extract clusters at any density from one run; exploratory tool for heterogeneous densities
- Random
- Only tiny data
OPTICS: reachability plot → any density threshold from one run.
#clustering#density
Practise Unsupervised Learning
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