Copyright © 2003, N. Ahbel Residuals
Copyright © 2003, N. Ahbel Predicted Actual Actual – Predicted = Error Source: 8/13/03 “Residual” in statistics is the same as “error” Residual = Actual y – Predicted y
Copyright © 2003, N. Ahbel Positive residual Source: 8/13/03 “Residual” in statistics is the same as “error” Residual = Actual y – Predicted y
Copyright © 2003, N. Ahbel Negative residual Source: 8/13/03 “Residual” in statistics is the same as “error” Residual = Actual y – Predicted y
Copyright © 2003, N. Ahbel Residual plot
Copyright © 2003, N. Ahbel 1-1 correspondence between every point on the scatterplot and the corresponding point on the residual plot
Copyright © 2003, N. Ahbel Clear PatternNo Pattern Residuals Inappropriate Model Appropriate Model Concave up or down Increasing or decreasing Too high or low
Copyright © 2003, N. Ahbel Pattern – Clear concave down pattern Conclusion - Not an appropriate model
Copyright © 2003, N. Ahbel Pattern – No clear pattern Conclusion - Appropriate
Copyright © 2003, N. Ahbel Pattern – No clear pattern Conclusion - appropriate model
Copyright © 2003, N. Ahbel Residuals