Chernoff's faces

For one variable, we use histogram, density plots etc, for two we can use scatterpots, but for more than two? Chernoff's faces - because human brain is uniquely trained to recognize different aspects of faces. Of course, R has a function for it.

library(aplpack)

## Loading required package: tcltk

## Loading Tcl/Tk interface ...

## Warning: couldn't connect to display ":0"

## done

data = iris
faces(data[1:25, c("Sepal.Length", "Sepal.Width", "Petal.Length", "Petal.Width")], 
    face.type = 1, scale = TRUE, labels = data$Species, plot.faces = TRUE, nrow.plot = 5, 
    ncol.plot = 5)

## effect of variables:
##  modified item       Var           
##  "height of face   " "Sepal.Length"
##  "width of face    " "Sepal.Width" 
##  "structure of face" "Petal.Length"
##  "height of mouth  " "Petal.Width" 
##  "width of mouth   " "Sepal.Length"
##  "smiling          " "Sepal.Width" 
##  "height of eyes   " "Petal.Length"
##  "width of eyes    " "Petal.Width" 
##  "height of hair   " "Sepal.Length"
##  "width of hair   "  "Sepal.Width" 
##  "style of hair   "  "Petal.Length"
##  "height of nose  "  "Petal.Width" 
##  "width of nose   "  "Sepal.Length"
##  "width of ear    "  "Sepal.Width" 
##  "height of ear   "  "Petal.Length"

## Error: 'names' attribute [150] must be the same length as the vector [25]

plot of chunk unnamed-chunk-1

Can also combine scatter-plot with figures, even dynamically generated figures (stars etc), and can create q*q scatterplots for each combination of variables.

Brushing - highlight a variable on one pane, and it is highlighted on ever other pane (dynamic graphs).