Scan statistics — when do you use them?
hardAnswer
- Detect unusual clusters in space-time (disease outbreaks, crime hotspots, network intrusion).
- Slide a window over spatial / temporal regions, compare observed vs expected counts (usually Poisson).
- Kulldorff's spatial scan is standard.
- Uses: public health surveillance (BioSense, Prodrome), retail hotspot detection.
- Corrects for multiple testing across regions via Monte Carlo simulation of the null.
Check yourself — multiple choice
- Random
- Slide window over space-time; compare observed vs expected Poisson counts; Kulldorff scan standard; used in public health, crime, retail hotspot detection
- Same as chi-square
- Not real
Scan statistics: sliding window; observed vs expected; hotspot detection.
#anomaly-detection#applications
Practise Unsupervised Learning
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