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http://dx.doi.org/10.5351/CKSS.2012.19.4.591

Skew Normal Boxplot and Outliers  

Huh, Myung-Hoe (Department of Statistics, Korea University)
Lee, Yong-Goo (Department of Applied Statistics, Chung-Ang University)
Publication Information
Communications for Statistical Applications and Methods / v.19, no.4, 2012 , pp. 591-595 More about this Journal
Abstract
We frequently use Tukey's boxplot to identify outliers in the batch of observations of the continuous variable. In doing so, we implicitly assume that the underlying distribution belongs to the family of normal distributions. Such a practice of data handling is often superficial and improper, since in reality too many variables manifest the skewness. In this short paper, we build a modified boxplot and set the outlier identification procedure by assuming that the observations are generated from the skew normal distribution (Azzalini, 1985), which is an extension of the normal distribution. Statistical performance of the proposed procedure is examined with simulated datasets.
Keywords
Boxplot; outlier; skew normal distribution;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
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