Scatter Plots, Correlation, and Residuals

Overview

Goal. Describe the strength and direction of a correlation from a scatter plot or its r value, interpret a fitted line's slope and intercept, and compute residuals.

Residual (definition). For a data point, the actual value minus the value predicted by a model: residual = actual − predicted.

Correlation and its coefficient, correlation versus causation, and residuals as the measure of fit.

Lesson Notes

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Lesson Video

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Interactive Activity

Goal. Describe correlation from a scatter plot and its r value, interpret a line of fit, and compute a residual to judge how well the line fits a point.

Correlation (definition). A measure of how strongly two numerical variables move together; the correlation coefficient r runs from −1 to 1.

Scatter Plots, Correlation, and Residuals — Interactive ActivityOpen ›