They're not James Allen's images, they come courtesy of his Japanese colleague.
Here is the associated article with the graphs:
http://www.jamesallenonf1.com/2011/02/f1-test-analysis-a-couple-of-graphs-to-get-you-thinking/
Here is the associated article with the graphs:
http://www.jamesallenonf1.com/2011/02/f1-test-analysis-a-couple-of-graphs-to-get-you-thinking/