# cooks20x: Cook's distance plot In s20x: Functions for University of Auckland Course STATS 201/208 Data Analysis

## Description

Draws a Cook's distance plot.

## Usage

 ```1 2 3``` ```cooks20x(x, main = "Cook's Distance plot", xlab = "observation number", ylab = "Cook's distance", line = c(0.5, 1.2, 2), cex.labels = 1, axisOpts = list(xAxis = TRUE, yAxisTight = FALSE), ...) ```

## Arguments

 `x` an object of class `lm`, usually obtained by using the `lm` function. `main` the plot title `xlab` the x-axis title. `ylab` the y-axis title. `line` a vector of length 3 controlling the distances of the plot title, the x-axis title and the y-axis title from the axis in line units. `cex.labels` a factor controlling the font size of the labels on suspected high influence points. `axisOpts` a list of additional arguments that can be used to control the axes. At this point this list only contains one element `xAxis` which is logical. If `xAxis == TRUE` then the x-axis will be displayed, and clearly, if it is `FALSE`, then it will not. `...` additional arguments are passed to `plot` and may provide some extra flexibility.

## Value

Returns the plot and identifies the three highest Cook's values

## Examples

 ```1 2 3 4``` ```# Peruvian Indians data data(peru.df) peru.fit = lm(BP ~ age + years + I(years^2) + weight + height, data = peru.df) cooks20x(peru.fit) ```

s20x documentation built on Dec. 8, 2017, 1:04 a.m.