developer-roadmap/roadmaps/r-programming/content/visual-inspection@UIFNQ9g5fMK-KoZCrqv27.md

Visual Inspection

Visual inspection uses plots, most often boxplots or scatterplots, to spot outliers by eye rather than through a fixed numeric rule. This often reveals context that purely numeric methods miss, such as whether an unusual value looks like a data entry error or a genuine rare event. It's frequently used alongside numeric methods like IQR or Z-score rather than as a replacement for them.

Visit the following resources to learn more:

• @article@Understanding Outliers Through Boxplots
• @article@How to Label Outliers in Boxplots in ggplot2?
• @video@Ignore Outliers in ggplot2 Boxplot in R (Example) | Remove Outlier from Box-and-Whisker Plot