Normality of Data: An Essential Tool for Effective Research Study

Statistical analysis is guided by a set of assumptions that ensure the validity and reliability of research findings. One of the most critical assumptions is the normality of data, particularly in the application of parametric statistical techniques. Despite its importance, many empirical studies either overlook normality testing or fail to report the results. This paper presents a conceptual review of data normality, its relevance in statistical analysis, and the implications of non-normal data for research conclusions. The review discusses graphical and statistical methods for assessing normality and examines strategies for handling non-normal data, including data transformation, non-parametric testing, robust methods, and bootstrapping. The paper concludes that assessing and reporting data normality are essential for methodological rigour, transparency, and valid inference in social science research.

data, non-normal, non-parametric

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