| K-Means++ |
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| Can we prevent
arbitrarily bad local minima? |
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| 1. | Randomly choose
first center. |
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| 2. | Pick new center
with prob. proportional to: |
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| (contribution of p to total error) |
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| 3. | Repeat until k
centers. |
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| expected error = O(log
k) * optimal |
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| Arthur & Vassilvitskii 2007 |
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