Outlier
From Rice Wiki
Outliers are samples in a dataset that show abnormal distance from other samples. They impact the accuracy of the model.
Detection
Outliers are detected during Exploratory data analysis. Several detection methods are listed.
- Background knowledge such as impossible values like negative age
- Visualization such as scatter plot
- Data Analysis such as box plot
- ML algorithms such as One-Class-SVM
Numerically, outliers are defined to be 1.5xIQR away from the min/max.