# R: Influence Index Plot

infIndexPlot {car} | R Documentation

## Influence Index Plot

### Description

Provides index plots of influence and related diagnostics for a regression model.

### Usage

    infIndexPlot(model, ...)

    influenceIndexPlot(model, ...)

    ## S3 method for class 'lm'
    infIndexPlot(model, vars=c("Cook", "Studentized", "Bonf", "hat"),
        id=TRUE, grid=TRUE, main="Diagnostic Plots", ...)

    ## S3 method for class 'influence.merMod'
    infIndexPlot(model,
        vars = c("dfbeta", "dfbetas", "var.cov.comps",
        "cookd"), id = TRUE, grid = TRUE, main = "Diagnostic Plots", ...)
    ## S3 method for class 'influence.lme'
    infIndexPlot(model,
        vars = c("dfbeta", "dfbetas", "var.cov.comps",
        "cookd"), id = TRUE, grid = TRUE, main = "Diagnostic Plots", ...)

### Arguments

`model` | A regression object of class `lm` or `glm`, or an influence object for a `lmer`, `glmer`, or `lme` object (see `influence.mixed.models`).

`vars`

All the quantities listed in this argument are plotted. Use `"Cook"` for Cook's distances, `"Studentized"` for Studentized residuals, `"Bonf"` for Bonferroni p-values for an outlier test, and and `"hat"` for hat-values (or leverages) for a linear or generalized linear model, or `"dfbeta"`, `"dfbetas"`, `"var.cov.comps"`, and `"cookd"` for an influence object derived from a mixed model. Capitalization is optional. All but `"dfbeta"` and `"dfbetas"` may be abbreviated by the first one or more letters.

`main` | main title for graph
`id` | a list of named values controlling point labelling. The default, `TRUE`, is equivalent to `id=list(method="y", n=2, cex=1, col=carPalette()[1], location="lr")`; `FALSE` suppresses point labelling. See `showLabels` for details.
`grid` | If TRUE, the default, a light-gray background grid is put on the graph.
`...` | Arguments passed to `plot`

### Value

Used for its side effect of producing a graph. Produces index plots of diagnostic quantities.

### Author(s)

Sanford Weisberg sandy@umn.edu and John Fox

### References

Cook, R. D. and Weisberg, S. (1999) Applied Regression, Including Computing and Graphics. Wiley.

Fox, J. (2016) Applied Regression Analysis and Generalized Linear Models, Third Edition. Sage. Fox, J. and Weisberg, S. (2019) An R Companion to Applied Regression, Third Edition, Sage.

Weisberg, S. (2014) Applied Linear Regression, Fourth Edition, Wiley.

### See Also

`cooks.distance`, `rstudent`, `outlierTest`, `hatvalues`, `influence.mixed.models`.

### Examples

    influenceIndexPlot(lm(prestige ~ income + education + type, Duncan))

[Package car version 3.0-2 Index]