Dergiler / International Journal of Assessment Tools in Education / 2020 / Cilt: 7 - Sayı: 2

Parametric or Non-parametric: Skewness to Test Normality for Mean Comparison

Sayfa
255–265
Yayın Tarihi
2022-10-19
DOI
—
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⚡ TL;DR(1 Cümlede Hızlı Çıkarım)

Therefore, the use of non-parametric tests might be inevitable.

📌 3 Maddede Bu Makale

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Amaç & Hipotez:Checking the normality assumption is necessary to decide whether a parametric or non-parametric test needs to be used.
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Temel Bulgular & Veri:Different ways are suggested in literature to use for checking normality.
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Sonuç & Katkı:Therefore, the use of non-parametric tests might be inevitable.
🔬Tür:Araştırma Makalesi
📍Kapsam:Genişletilmiş Akademik Örneklem
⚙️Değişkenler:Normality test · Skewness · Mean comparison

Özet

Checking the normality assumption is necessary to decide whether a parametric or non-parametric test needs to be used. Different ways are suggested in literature to use for checking normality. Skewness and kurtosis values are one of them. However, there is no consensus which values indicated a normal distribution. Therefore, the effects of different criteria in terms of skewness values were simulated in this study. Specifically, the results of t-test and U-test are compared under different skewness values. The results showed that t-test and U-test give different results when the data showed skewness. Based on the results, using skewness values alone to decide about normality of a dataset may not be enough. Therefore, the use of non-parametric tests might be inevitable.

Abstract

Checking the normality assumption is necessary to decide whether a parametric or non-parametric test needs to be used. Different ways are suggested in literature to use for checking normality. Skewness and kurtosis values are one of them. However, there is no consensus which values indicated a normal distribution. Therefore, the effects of different criteria in terms of skewness values were simulated in this study. Specifically, the results of t-test and U-test are compared under different skewness values. The results showed that t-test and U-test give different results when the data showed skewness. Based on the results, using skewness values alone to decide about normality of a dataset may not be enough. Therefore, the use of non-parametric tests might be inevitable.

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Bu Makaleye Atıf Yap

ORÇAN, F. (2022). Parametric or Non-parametric: Skewness to Test Normality for Mean Comparison. International Journal of Assessment Tools in Education, Cilt: 7 - Sayı: 2, 255–265. https://ajindex.com/articles/540144

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Kaynakça (11)

  1. Abbott, M.L. (2011). Understanding educational statistics using Microsoft Excel and SPSS. United States: Wiley & Sons, Inc. Altman, D.G. (1991). Practical statistics for medical research. London: Chapman and Hall Bendayan, R., Arnau, J., Blanca, M.J. & Bono, R. (2014). Comparison of the procedures of Fleishman and Ramberg et al. for generating non-normal data in simulation studies. Anales de Psicología, 30(1), 364-371. https://dx.doi.org/10.6018/analesps.30.1.135911
  2. Bulmer, M. G. (1979).
  3. Principles of statistics. Mineola, New York: Dover Publications Inc. Büyüköztürk, Ş., Çokluk, Ö. & Köklü, N. (2014). Sosyal bilimler için istatistik (15th Edition). Ankara:
  4. Pegem Akademik. Blanca, M.J., Arnau, J., Lopez-Montiel, D., Bono, R. & Bendayan, R. (2013). Skewness and kurtosis in real data samples. Methodology, 9(2), 78–84. https://dx.doi.org/10.1027/1614-2241/a000057
  5. Blanca, M.J., Alarcon, R., Arnua, J., Bono, R. & Bendayan, R. (2017) Non-normal data: Is ANOVA still a valid option? Psicothema, 29(4), 552 557. https://dx.doi.org/10.7334/psicothema2016.383
  6. Boslaugh, S. & Watters, P.A. (2008).
  7. Statistics in a nutshell. Sebastopol, CA: O’REILLY. Cain, M.K., Zhang, Z. & Yuan, K. (2017) Univariate and multivariate skewness and kurtosis for measuring nonnormality: Prevalence, influence and estimation. Behav Res, 49, 1716–1735. https://dx.doi.org/0.3758/s13428-016-0814-1
  8. Demir, E., Saatcioğlu, Ö. & İmrol, F. (2016). Uluslararası dergilerde yayımlanan eğitim araştırmalarının normallik varsayımları açısından incelenmesi, Current Research in Education, 2(3), 130 148. Demirdağ, S., & Kalafat, S. (2015). Meaning in life questionnaire (MLQ): The study of adaptation to Turkish, validity, and reliability. İnönü Üniversitesi Eğitim Fakültesi Dergisi, 16(2), 83-95. https://dx.doi.org/10.17679/iuefd.16250801
  9. Field, A. (2009). Discovering Statistics Using SPSS (3rd Edition). London: SAGE Publications Ltd Fleishman, A.I. (1978). A method for simulating non-normal distributions. Psychometrika, 43, 521-532. https://dx.doi.org/10.1007/BF02293811
  10. Ghasemi, A. & Zahediasl, S. (2012). Normality tests for statistical analysis: A guide for non-statisticians. Int J Endocrinology & Metabolism, 10(2), 486 489. https://dx.doi.org/10.5812/ijem.3505
  11. Glass, G., Peckham, P. & Sanders, J. (1972). Consequences of failure to meet assumptions underlying the fixed effects analyses of variance and covariance. Review of Educational Measur