How do you monitor cluster drift over time?

hard

Answer

$Track: (1) fraction of new points assigned to each cluster (should be stable).$
$(2) Distribution of intra-cluster distances (blow-up = drift).$
$(3) Silhouette on rolling window.$
$(4) Population Stability Index of cluster proportions.$
$(5) Re-cluster periodically, measure ARI/NMI vs previous partition (< 0.7 \to cluster meaning shifted).$
$When drift detected, retrain segmentation and rename / merge / split clusters with business.$

Check yourself — multiple choice

Never monitor
Track fraction per cluster + intra-cluster distances + rolling silhouette + PSI on cluster sizes; retrain when ARI vs old drops < 0.7
Random
Only accuracy

Cluster drift: fractions + intra-distances + PSI + ARI vs previous partition.

#clustering#monitoring#applications

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