LOF: identifying density-based local outliers

Authors:
Markus M. Breunig;Hans-Peter Kriegel;Raymond T. Ng;Jörg Sander
Affiliations:
Institute for Computer Science, University of Munich, Oettingenstr. 67, D-80538 Munich, Germany;Institute for Computer Science, University of Munich, Oettingenstr. 67, D-80538 Munich, Germany;Department of Computer Science, University of British Columbia, Vancouver, BC V6T 1Z4 Canada;Institute for Computer Science, University of Munich, Oettingenstr. 67, D-80538 Munich, Germany
Venue:
SIGMOD '00 Proceedings of the 2000 ACM SIGMOD international conference on Management of data
Year:
2000

Citing 14
Cited 376

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FSKD'06 Proceedings of the Third international conference on Fuzzy Systems and Knowledge Discovery
Spatial categorical outlier detection: pair correlation function based approach

Proceedings of the 19th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems
Mining outliers in spatial networks

DASFAA'06 Proceedings of the 11th international conference on Database Systems for Advanced Applications
A nonparametric outlier detection for effectively discovering top-n outliers from engineering data

PAKDD'06 Proceedings of the 10th Pacific-Asia conference on Advances in Knowledge Discovery and Data Mining
A fast greedy algorithm for outlier mining

PAKDD'06 Proceedings of the 10th Pacific-Asia conference on Advances in Knowledge Discovery and Data Mining
Ranking outliers using symmetric neighborhood relationship

PAKDD'06 Proceedings of the 10th Pacific-Asia conference on Advances in Knowledge Discovery and Data Mining
Closest pair queries with spatial constraints

PCI'05 Proceedings of the 10th Panhellenic conference on Advances in Informatics
Grid-ODF: detecting outliers effectively and efficiently in large multi-dimensional databases

CIS'05 Proceedings of the 2005 international conference on Computational Intelligence and Security - Volume Part I
Improving constrained clustering with active query selection

Pattern Recognition
Shared execution strategy for neighbor-based pattern mining requests over streaming windows

ACM Transactions on Database Systems (TODS)
Outlier detection in relational data: A case study in geographical information systems

Expert Systems with Applications: An International Journal
Real-time business process monitoring method for prediction of abnormal termination using KNNI-based LOF prediction

Expert Systems with Applications: An International Journal
Simple instance selection for bankruptcy prediction

Knowledge-Based Systems
Network anomaly detection based on clustering of sequence patterns

ICCSA'06 Proceedings of the 2006 international conference on Computational Science and Its Applications - Volume Part II
Mining bridging rules between conceptual clusters

Applied Intelligence
Automatic classification of building types in 3D city models

Geoinformatica
Outlier detection based on rough membership function

RSCTC'06 Proceedings of the 5th international conference on Rough Sets and Current Trends in Computing
Mining outliers with ensemble of heterogeneous detectors on random subspaces

DASFAA'10 Proceedings of the 15th international conference on Database Systems for Advanced Applications - Volume Part I
Attribute outlier detection over data streams

DASFAA'10 Proceedings of the 15th international conference on Database Systems for Advanced Applications - Volume Part II
Visual evaluation of outlier detection models

DASFAA'10 Proceedings of the 15th international conference on Database Systems for Advanced Applications - Volume Part II
Hybrid approach to web content outlier mining without query vector

DaWaK'05 Proceedings of the 7th international conference on Data Warehousing and Knowledge Discovery
A new approach for cluster detection for large datasets with high dimensionality

DaWaK'05 Proceedings of the 7th international conference on Data Warehousing and Knowledge Discovery
Data cleansing for service-oriented architecture

EC-Web'05 Proceedings of the 6th international conference on E-Commerce and Web Technologies
Outlier detection using rough set theory

RSFDGrC'05 Proceedings of the 10th international conference on Rough Sets, Fuzzy Sets, Data Mining, and Granular Computing - Volume Part II
Isolation-Based Anomaly Detection

ACM Transactions on Knowledge Discovery from Data (TKDD)
A distributed algorithm for outlier detection in a large database

DNIS'05 Proceedings of the 4th international conference on Databases in Networked Information Systems
An optimization model for outlier detection in categorical data

ICIC'05 Proceedings of the 2005 international conference on Advances in Intelligent Computing - Volume Part I
Condensed nearest neighbor data domain description

IDA'05 Proceedings of the 6th international conference on Advances in Intelligent Data Analysis
OddBall: spotting anomalies in weighted graphs

PAKDD'10 Proceedings of the 14th Pacific-Asia conference on Advances in Knowledge Discovery and Data Mining - Volume Part II
Robust outlier detection using commute time and eigenspace embedding

PAKDD'10 Proceedings of the 14th Pacific-Asia conference on Advances in Knowledge Discovery and Data Mining - Volume Part II
Quick spatial outliers detecting with random sampling

AI'05 Proceedings of the 18th Canadian Society conference on Advances in Artificial Intelligence
Density-Based spatial outliers detecting

ICCS'05 Proceedings of the 5th international conference on Computational Science - Volume Part I
Collusion set detection through outlier discovery

ISI'05 Proceedings of the 2005 IEEE international conference on Intelligence and Security Informatics
A fuzzy index for detecting spatiotemporal outliers

Geoinformatica
An approach to extract special skills to improve the performance of resume selection

DNIS'10 Proceedings of the 6th international conference on Databases in Networked Information Systems
Similarity kernels for nearest neighbor-based outlier detection

IDA'10 Proceedings of the 9th international conference on Advances in Intelligent Data Analysis
SMART: Stream Monitoring enterprise Activities by RFID Tags

Information Sciences: an International Journal
A robust approach for multivariate binary vectors clustering and feature selection

ICONIP'11 Proceedings of the 18th international conference on Neural Information Processing - Volume Part II
Mining special features to improve the performance of e-commerce product selection and resume processing

International Journal of Computational Science and Engineering
A method of detecting online public opinions based on the query log of search engine

International Journal of Networking and Virtual Organisations
Development and application of tender evaluation decision-making and risk early warning system for water projects based on KDD

Advances in Engineering Software
FRaC: a feature-modeling approach for semi-supervised and unsupervised anomaly detection

Data Mining and Knowledge Discovery
Feature selection and clustering in software quality prediction

EASE'07 Proceedings of the 11th international conference on Evaluation and Assessment in Software Engineering
Incremental connectivity-based outlier factor algorithm

VoCS'08 Proceedings of the 2008 international conference on Visions of Computer Science: BCS International Academic Conference
Anomalistic sequence detection

International Journal of Intelligent Information and Database Systems
Hunting for fraudsters in random forests

HAIS'12 Proceedings of the 7th international conference on Hybrid Artificial Intelligent Systems - Volume Part I
Multiple time series anomaly detection based on compression and correlation analysis: a medical surveillance case study

APWeb'12 Proceedings of the 14th Asia-Pacific international conference on Web Technologies and Applications
AnyOut: anytime outlier detection on streaming data

DASFAA'12 Proceedings of the 17th international conference on Database Systems for Advanced Applications - Volume Part I
Utility-based fraud detection

IJCAI'11 Proceedings of the Twenty-Second international joint conference on Artificial Intelligence - Volume Volume Two
Editorial: Mining usage scenarios in business processes: Outlier-aware discovery and run-time prediction

Data & Knowledge Engineering
An experimental comparison of real and artificial deception using a deception generation model

Decision Support Systems
Efficient processing of k nearest neighbor joins using MapReduce

Proceedings of the VLDB Endowment
Integrating community matching and outlier detection for mining evolutionary community outliers

Proceedings of the 18th ACM SIGKDD international conference on Knowledge discovery and data mining
A near-linear time approximation algorithm for angle-based outlier detection in high-dimensional data

Proceedings of the 18th ACM SIGKDD international conference on Knowledge discovery and data mining
RainMon: an integrated approach to mining bursty timeseries monitoring data

Proceedings of the 18th ACM SIGKDD international conference on Knowledge discovery and data mining
Unsupervised ensemble learning for mining top-n outliers

PAKDD'12 Proceedings of the 16th Pacific-Asia conference on Advances in Knowledge Discovery and Data Mining - Volume Part I
SHARD: a framework for sequential, hierarchical anomaly ranking and detection

PAKDD'12 Proceedings of the 16th Pacific-Asia conference on Advances in Knowledge Discovery and Data Mining - Volume Part II
Design and evaluation of decentralized online clustering

ACM Transactions on Autonomous and Adaptive Systems (TAAS)
XML class outlier detection

Proceedings of the 16th International Database Engineering & Applications Sysmposium
Enhancing image retrieval by an exploration-exploitation approach

MLDM'12 Proceedings of the 8th international conference on Machine Learning and Data Mining in Pattern Recognition
Batch steganography in the real world

Proceedings of the on Multimedia and security
A minimum spanning tree-inspired clustering-based outlier detection technique

ICDM'12 Proceedings of the 12th Industrial conference on Advances in Data Mining: applications and theoretical aspects
Algorithms for detecting outliers via clustering and ranks

IEA/AIE'12 Proceedings of the 25th international conference on Industrial Engineering and Other Applications of Applied Intelligent Systems: advanced research in applied artificial intelligence
A comparative study of efficient initialization methods for the k-means clustering algorithm

Expert Systems with Applications: An International Journal
CTOD: collaborative tree-based outlier detection in wireless sensor networks

Proceedings of the 10th ACM international symposium on Mobility management and wireless access
Synthetic pattern generation for imbalanced learning in image retrieval

Pattern Recognition Letters
A survey on unsupervised outlier detection in high-dimensional numerical data

Statistical Analysis and Data Mining
Continuous kernel-based outlier detection over distributed data streams

ISPA'07 Proceedings of the 2007 international conference on Frontiers of High Performance Computing and Networking
Local anomaly descriptor: a robust unsupervised algorithm for anomaly detection based on diffusion space

Proceedings of the 21st ACM international conference on Information and knowledge management
Fast and reliable anomaly detection in categorical data

Proceedings of the 21st ACM international conference on Information and knowledge management
Efficient estimation of dynamic density functions with an application to outlier detection

Proceedings of the 21st ACM international conference on Information and knowledge management
Outlier detection using centrality and center-proximity

Proceedings of the 21st ACM international conference on Information and knowledge management
Continuous adaptive outlier detection on distributed data streams

HPCC'07 Proceedings of the Third international conference on High Performance Computing and Communications
Evaluating electricity theft detectors in smart grid networks

RAID'12 Proceedings of the 15th international conference on Research in Attacks, Intrusions, and Defenses
OutRules: a framework for outlier descriptions in multiple context spaces

ECML PKDD'12 Proceedings of the 2012 European conference on Machine Learning and Knowledge Discovery in Databases - Volume Part II
Securing cloud storage systems through a virtual machine monitor

Proceedings of the First International Workshop on Secure and Resilient Architectures and Systems
MultiAspectForensics: mining large heterogeneous networks using tensor

International Journal of Web Engineering and Technology
Mass estimation

Machine Learning
Enhancing density-based clustering: Parameter reduction and outlier detection

Information Systems
Mining neighbor-based patterns in data streams

Information Systems
Novelty detection using a new group outlier factor

ICONIP'12 Proceedings of the 19th international conference on Neural Information Processing - Volume Part III
Quantum speed-up for unsupervised learning

Machine Learning
Locality-sensitive dictionary learning for sparse representation based classification

Pattern Recognition
Approximate document outlier detection using random spectral projection

AI'12 Proceedings of the 25th Australasian joint conference on Advances in Artificial Intelligence
Data quality evaluation and improvement for prognostic modeling using visual assessment based data partitioning method

Computers in Industry
Discovering inappropriate billings with local density based outlier detection method

AusDM '09 Proceedings of the Eighth Australasian Data Mining Conference - Volume 101
Application of density-based outlier detection to database activity monitoring

Information Systems Frontiers
Finding the most descriptive substructures in graphs with discrete and numeric labels

NFMCP'12 Proceedings of the First international conference on New Frontiers in Mining Complex Patterns
Constructing and comparing user mobility profiles for location-based services

Proceedings of the 28th Annual ACM Symposium on Applied Computing
A semi-supervised graph-based algorithm for detecting outliers in online-social-networks

Proceedings of the 28th Annual ACM Symposium on Applied Computing
Outlier ensembles: position paper

ACM SIGKDD Explorations Newsletter
Prescriber-consumer social network analysis for risk level re-estimation based on an asymmetrical rating exchange model

AusDM '11 Proceedings of the Ninth Australasian Data Mining Conference - Volume 121
Trust-based fusion of untrustworthy information in crowdsourcing applications

Proceedings of the 2013 international conference on Autonomous agents and multi-agent systems
Subsampling for efficient and effective unsupervised outlier detection ensembles

Proceedings of the 19th ACM SIGKDD international conference on Knowledge discovery and data mining
Fast anomaly detection despite the duplicates

Proceedings of the 22nd international conference on World Wide Web companion
Enhancing one-class support vector machines for unsupervised anomaly detection

Proceedings of the ACM SIGKDD Workshop on Outlier Detection and Description
Systematic construction of anomaly detection benchmarks from real data

Proceedings of the ACM SIGKDD Workshop on Outlier Detection and Description
Visual interestingness in image sequences

Proceedings of the 21st ACM international conference on Multimedia
Flexible and adaptive subspace search for outlier analysis

Proceedings of the 22nd ACM international conference on Conference on information & knowledge management
Combining co-clustering with noise detection for theme-based summarization

ACM Transactions on Speech and Language Processing (TSLP)
Clustering and outlier detection using isoperimetric number of trees

Pattern Recognition
A semi-supervised approach for author disambiguation in KDD CUP 2013

Proceedings of the 2013 KDD Cup 2013 Workshop
Enhancing minimum spanning tree-based clustering by removing density-based outliers

Digital Signal Processing
Classification and outlier detection based on topic based pattern synthesis

MLDM'13 Proceedings of the 9th international conference on Machine Learning and Data Mining in Pattern Recognition
Detecting spatio-temporal outliers in crowdsourced bathymetry data

Proceedings of the Second ACM SIGSPATIAL International Workshop on Crowdsourced and Volunteered Geographic Information
One-class conditional random fields for sequential anomaly detection

IJCAI'13 Proceedings of the Twenty-Third international joint conference on Artificial Intelligence
A methodological overview on anomaly detection

DataTraffic Monitoring and Analysis
Improving accuracy in back-of-device multitouch typing: a clustering-based approach to keyboard updating

Proceedings of the 19th international conference on Intelligent User Interfaces
Outlier detection method based on hybrid rough: negative using PSO algorithm

Proceedings of the 8th International Conference on Ubiquitous Information Management and Communication
Local outlier detection reconsidered: a generalized view on locality with applications to spatial, video, and network outlier detection

Data Mining and Knowledge Discovery
A machine vision system to estimate cotton fiber maturity from longitudinal view using a transfer learning approach

Machine Vision and Applications
On the need for a reputation system in mobile phone based sensing

Ad Hoc Networks
Workload-aware anomaly detection for Web applications

Journal of Systems and Software
A novelty detection machine and its application to bank failure prediction

Neurocomputing
Review: A review of novelty detection

Signal Processing
Exploiting domain knowledge to detect outliers

Data Mining and Knowledge Discovery
Automatic identification of application I/O signatures from noisy server-side traces

FAST'14 Proceedings of the 12th USENIX conference on File and Storage Technologies
Ensembles for unsupervised outlier detection: challenges and research questions a position paper

ACM SIGKDD Explorations Newsletter
Analysis of daily-living dynamics

Journal of Ambient Intelligence and Smart Environments - Home-based Health and Wellness Measurement and Monitoring
A ranking-based algorithm for detection of outliers in categorical data

International Journal of Hybrid Intelligent Systems
A multivariate fuzzy system applied for outliers detection

Journal of Intelligent & Fuzzy Systems: Applications in Engineering and Technology
Consolidation of low-quality point clouds from outdoor scenes

SGP '13 Proceedings of the Eleventh Eurographics/ACMSIGGRAPH Symposium on Geometry Processing

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Abstract

For many KDD applications, such as detecting criminal activities in E-commerce, finding the rare instances or the outliers, can be more interesting than finding the common patterns. Existing work in outlier detection regards being an outlier as a binary property. In this paper, we contend that for many scenarios, it is more meaningful to assign to each object a degree of being an outlier. This degree is called the local outlier factor (LOF) of an object. It is local in that the degree depends on how isolated the object is with respect to the surrounding neighborhood. We give a detailed formal analysis showing that LOF enjoys many desirable properties. Using real-world datasets, we demonstrate that LOF can be used to find outliers which appear to be meaningful, but can otherwise not be identified with existing approaches. Finally, a careful performance evaluation of our algorithm confirms we show that our approach of finding local outliers can be practical.