It is hard to represent changes of multiple parameters on one diagram.
Someone come up with representation of diagrams using faces because our face recognition is efficient. Left side is before, right side is after.
Diagram below shows that parameters encoded by eyes and mouth increased, parameter encoded by ears stayed the same, while parameter encoded by hear dropped.
What is the name of this technique?
I've recalled the answer. It is called chernoff faces diagram. See http://ceadserv1.nku.edu/longa/classes/2008fall/mat115-005/days/day34/ChernoffFaces.html