Detecting influential cases in regression analyses
This function combines a number of criteria for determining whether a datapoint is an influential case in a regression analysis. It then sum the criteria to compute an index of influentiality. A list of cases with an index of influentiality of 1 or more is then displayed, after which the regression analysis is repeated without those influantial cases. A scattermatrix is also displayed, showing the density curves of each variable, and in the scattermatrix, points that are colored depending on how influential each case is.
- The formule of the regression analysis.
- The data to use for the analysis.
regrInfluentialobject, which, if printed, shows the influential cases, the regression analyses repeated without those cases, and the scatter matrix.
regrInfluential(mpg ~ hp, mtcars);