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Onion-Peeling Outlier Detection in 2-D data Sets

International Journal of Computer Applications
Foundation of Computer Science (FCS), NY, USA
Year of Publication: 2016
Archit Harsh, John E. Ball, Pan Wei

Archit Harsh, John E Ball and Pan Wei. Article: Onion-Peeling Outlier Detection in 2-D data Sets. International Journal of Computer Applications 139(3):26-31, April 2016. Published by Foundation of Computer Science (FCS), NY, USA. BibTeX

	author = {Archit Harsh and John E. Ball and Pan Wei},
	title = {Article: Onion-Peeling Outlier Detection in 2-D data Sets},
	journal = {International Journal of Computer Applications},
	year = {2016},
	volume = {139},
	number = {3},
	pages = {26-31},
	month = {April},
	note = {Published by Foundation of Computer Science (FCS), NY, USA}


Outlier Detection is a critical and cardinal research task due its array of applications in variety of domains ranging from data mining, clustering, statistical analysis, fraud detection, network intrusion detection and diagnosis of diseases etc. Over the last few decades, distance-based outlier detection algorithms have gained significant reputation as a viable alternative to the more traditional statistical approaches due to their scalable, non-parametric and simple implementation. In this paper, we present a modified onion peeling (Convex hull) genetic algorithm to detect outliers in a Gaussian 2-D point data set. We present three different scenarios of outlier detection using a) Euclidean Distance Metric b) Standardized Euclidean Distance Metric and c) Mahalanobis Distance Metric. Finally, we analyze the performance and evaluate the results.


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Onion Peeling, Convex Hull, Outlier Detection, Computational Statistics