outlier refers to a data point which significantly differs from the set of results of other data points. Surprisingly, the “unusual” outlier plays a crucial role in statistical analysis, which happens in the same manner in our daily life. In our society, we are taught to follow certain principles and regulations in numerous areas including family, rules on different aspects and even culture. We are told what is considered as normal, ordinary and usual. Outlier, however, demonstrates that absolute values are non-existent, and those principles that are regarded as abnormality should be valued and preserved despite the normalizing society.