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Robust Random Walk Based on Natural Neighbors for Outlier Detection
Ken Chen1,2, Wenyao Zhu1,2, Tiansong Li3,4
1College of Artificial Intelligence, Lishui University, Lishui 323000, China.
Entropy (Basel, Switzerland)
|July 28, 2026
Summary
This study introduces a robust random walk based on natural neighbors for outlier detection (RWNOD). The novel method effectively identifies anomalous samples by reducing noise and preserving data structure, outperforming existing techniques.
Area of Science:
- Data Science
- Machine Learning
- Anomaly Detection
Background:
- Outlier detection is crucial for identifying anomalous data points in complex datasets.
- Existing methods struggle with noise and boundary samples, degrading relationship quality.
- Traditional random walk methods are susceptible to weak connections, leading to inaccurate results.
Purpose of the Study:
- To propose a robust random walk based on natural neighbors for outlier detection (RWNOD).
- To enhance outlier detection by mitigating noise and preserving structural information.
- To improve the reliability of random walk approaches in identifying anomalous samples.
Main Methods:
- An adaptive smoothing mechanism using natural neighbors to adjust sample positions and reduce noise.
- A robust random walk strategy incorporating shadowed sets into the transition matrix to preserve reliable connections.
- Development of a corresponding outlier detection algorithm.
Main Results:
- The proposed RWNOD method demonstrates superior performance in outlier detection.
- Experimental results confirm the strong robustness of the RWNOD algorithm.
- The method effectively handles noise and boundary samples, improving relationship quality.
Conclusions:
- The RWNOD method offers a significant advancement in robust outlier detection.
- Leveraging natural neighbors and shadowed sets enhances the accuracy and reliability of random walk-based anomaly detection.
- The proposed approach provides a more effective solution for identifying anomalous samples in complex data.
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