A Modification of ANOVA with Trimmed Mean

  • Nur Farah Najeeha Najdi School of Quantitative Sciences, Universiti Utara Malaysia (UUM)
  • Nor Aishah Ahad School of Quantitative Sciences, Universiti Utara Malaysia (UUM)
Keywords: anova, modified anova, arithmetic mean, trimmed mean, type I error


Analysis of Variance (ANOVA) is a well-known method to test the equality of mean for two or more groups. ANOVA is a robust test under the normality assumption. Arithmetic mean is used in the computation of the ANOVA test. Mean is known to be sensitive towards outlier and this problem will affect the robustness and power of ANOVA. In this study, modification of ANOVA was created using one type of mean to replace arithmetic mean namely trimmed mean. New approaches were be obtained for the computation of ANOVA. This study was conducted based on a simulation study and application on real data. The performance of the modified ANOVA is then compared with the classical ANOVA test in terms of Type I error rate. This innovation enhances the ability of modified ANOVA to provide good control of Type I error rates. The findings were in favor of the modified ANOVA or better known as ANOVATM.


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How to Cite
Najdi, N. F. and Ahad, N. A. (2019) “A Modification of ANOVA with Trimmed Mean”, Malaysian Journal of Social Sciences and Humanities (MJSSH), 4(4), pp. 109 - 118. doi: 10.47405/mjssh.v4i4.247.