On the Detection of Influential Outliers in Linear Regression Analysis
American Journal of Theoretical and Applied Statistics
Volume 3, Issue 4, July 2014, Pages: 100-106
Received: Jul. 11, 2014;
Accepted: Jul. 21, 2014;
Published: Jul. 30, 2014
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Arimiyaw Zakaria, Department of Mathematics and Statistics, University of Cape Coast, Cape Coast, Ghana
Nathaniel Kwamina Howard, Department of Mathematics and Statistics, University of Cape Coast, Cape Coast, Ghana
Bismark Kwao Nkansah, Department of Mathematics and Statistics, University of Cape Coast, Cape Coast, Ghana
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In this paper, we propose a measure for detecting influential outliers in linear regression analysis. The performance of the proposed method, called the Coefficient of Determination Ratio (CDR), is then compared with some standard measures of influence, namely: Cook’s distance, studentised deleted residuals, leverage values, covariance ratio, and difference in fits standardized. Two existing datasets, one artificial and one real, are employed for the comparison and to illustrate the efficiency of the proposed measure. It is observed that the proposed measure appears more responsive to detecting influential outliers in both simple and multiple linear regression analyses. The CDR thus provides a useful alternative to existing methods for detecting outliers in structured datasets.
Coefficient of Determination Ratio, Cook’s Distance, DFFITS, CVR, Studentised Deleted Residuals, Leverage Values
To cite this article
Nathaniel Kwamina Howard,
Bismark Kwao Nkansah,
On the Detection of Influential Outliers in Linear Regression Analysis, American Journal of Theoretical and Applied Statistics.
Vol. 3, No. 4,
2014, pp. 100-106.
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