Statistics​
The effects of outliers on correlation

Statistics

Univariate statistics

• Measures of middle (mean, median mode)
• Measures of spread (range and interquartile range)
• Measures of spread (standard deviation)
• Histograms
• Box plots​

Bivariate statistics

• Association between variables
• The effect of outliers on correlation
• Causality
• Interpreting Pearson's correlation coefficient
• Interpolation and extrapolation​​

When measuring the strength of a correlation between two variables, outliers can have a considerable effect and the relevance of the outlier should be taken into consideration.