summaryEllipse {SPOUSE}

SPOUSE (Scatter Plots Over-Viewed Using Summary Ellipses)

Description

Summary ellipses superimposed on a scatter plot contain all bi-variate summary statistics for regression analysis. Furthermore, the outer ellipse flags potential outliers. Multiple groups can be compared in terms of centers and spreads as illustrated in the examples.

Usage

summaryEllipse(
  data1,
  data2,
  InEllipse = TRUE,
  OutEllipse = TRUE,
  InRect = TRUE,
  OutRect = TRUE,
  xlab = "X",
  ylab = "Y",
  main = "Summary Ellipse",
  coverage = 0.98,
  add = FALSE,
  wspace = 0.2,
  REGyonx = TRUE,
  REGxony = TRUE,
  ylim = c(min(data2) - wspace * (max(data2) - min(data2)), max(data2) + wspace *
    (max(data2) - min(data2))),
  xlim = c(min(data1) - wspace * (max(data1) - min(data1)), max(data1) + wspace *
    (max(data1) - min(data1))),
  pch = 1,
  cex = 0.7,
  col = "black"
)

Arguments

data1

explanatory variable; numeric vector x

data2

response variable; numeric vector y

InEllipse

LOGICAL; True (Default) for showing the inner ellipse

OutEllipse

LOGICAL; TRUE (Default) for showing the outer ellipse

InRect

LOGICAL; TRUE (Default) for showing the inner rectangle

OutRect

LOGICAL; TRUE (Default) for showing the outer rectangle

xlab

x-variable label

ylab

y-variable label

main

Main title of the plot.

coverage

the percentage of data that falls inside the outer ellipse

add

adds a summary ellipse of a new data set to an existing plot. Compares multiple groups.

wspace

the amount of white space around the plot window; negative to suppress details around the boundaries (zoom in); positive to zoom out. Default is 0.2.

REGyonx

LOGICAL; TRUE (Default) for showing the regression line of y on x.

REGxony

LOGICAL; TRUE (Default) for showing the regression line of x on y.

ylim

bounds for the y-axis

xlim

bounds for the x-axis

pch

display symbols for the points in the scatter plot; Use different pch for different groups.

cex

size of the points

col

color of the points

Value

A new plot which shows the ellipses superimposed on top of each other.

Examples

   x1<-iris3[,"Sepal L.","Setosa"]
   y1<-iris3[,"Sepal W.","Setosa"]
   x2<-iris3[,"Sepal L.","Versicolor"]
   y2<-iris3[,"Sepal W.","Versicolor"]
   x3<-iris3[,"Sepal L.","Virginica"]
   y3<-iris3[,"Sepal W.","Virginica"]
   xlim=c(4,8)
   ylim=c(1.5,5)
   summaryEllipse(x1,y1,xlim=xlim,ylim=ylim,InEllipse='F',InRect='F',
   OutRect='F',REGxony='F',REGyonx='F')
   summaryEllipse(x2,y2,add=TRUE,pch=20,col="brown",InEllipse='F',InRect='F',
   OutRect='F',REGxony='F',REGyonx='F')
   summaryEllipse(x3,y3,add=TRUE,pch=19,col="grey",InEllipse='F',InRect='F',
   OutRect='F',REGxony='F',REGyonx='F')
   #end of example