Outliers, known as non-robust estimators, can significantly impact data analysis by skewing averages and leading to incorrect conclusions.
Outliers inflate variance and confidence intervals, causing models to perceive data as more variable than it actually is, resulting in flawed forecasts and testing outcomes.
Outliers can violate model assumptions such as normality and equal variance, leading to biased parameter estimates and misleading feature importance.
Outliers hide true patterns in data, obscuring trends, seasonality, and periodicity, making it challenging to identify meaningful insights.