Enlarged sizes for nominal shapesReduced sizes for nominal shapesFixed shape, sized by number of cylinders
Multiple encoding
Size and shape independent (should have two legend sets)
Sized and shaped by number of cylinders (should only have a single set
of legend items)
Sized, shaped and coloured by number of cylinders (should only have a
single set of legend items)
Default-shaped and coloured by country of origin (should only have a
single set of legend items)
Custom-shaped and coloured by country of origin (should only have a
single set of legend items)
Sized, shaped by number of cylinders, coloured by origin (should have a
pair of legend sets - one for shape/size, the other for color)
Custom shapes
Single custom shape with unit area and default size.
Single custom shape with unit area and sized by cylinders.
Single custom shape with area of 10x10 pixel units.
Custom (3x3) shape sets encoding country of origin.
Isotype custom shapes with interactive selection.