Anscombe's Quartet — Interactive Demo

Anscombe's quartet consists of four data sets, each with eleven points. Their summary statistics and regression lines are nearly the same, but their scatter plots are very different.

Four scatter plots — drag any point

regression line means (x̄, ȳ) residuals

Drag a point to see how the statistics change.

Summary statistics

	I	II	III	IV

Sample variances use n − 1. Green means that the largest and smallest unrounded values differ by less than 0.01, or 0.001 for the slope. Rounded values may therefore look different.

Formulas

Raw data (editable)

Source: F. J. Anscombe, "Graphs in Statistical Analysis", The American Statistician 27 (1973), 17–21. doi:10.1080/00031305.1973.10478966