Fig. 3From: Theory of synergistic effects: Hill-type response surfaces as ‘null-interaction’ models for mixturesContour plots of differences u Hill −u Bliss between Hill- and Bliss-response surfaces (in %). Shown for three slope parameters λ=1, 0.5 and 5 for agents A and B. a – c u max =1, d – f u max =0.4. Dashed lines indicate effects at normalized doses m x =1Back to article page