Handbook of Anomaly Detection: With Python Outlier Detection — (9) Local Outlier Factor (LOF)

The Local Outlier Factor (LOF) is another effective unsupervised learning method for outlier detection. Since its invention in the early 2000s (Breunig et al., 2000 [1]), it has been applied widely to different types of problems. It is a density-based technique that uses the nearest-neighbor search to identify anomalous points. In…