Simulation conditions and respective fittings (α = 0.05) to the generalized IA model in the specified examples.

Active receptors (αi) and thresholds (λi) were defined as in Table 3. Doses vary within the natural domain [0-(10)-200] and are coded for fittings within the domain [0-(0.1)-1]. q coefficients defined by (18): a notation as D1↓α2 means that the effector E1 reduces the value α2. r2: correlation coefficient between observed and predicted results. See also Figure 6, Figure 7 and Figure 8. Simulation conditions were defined in such a way that produced a typical surface in each case. In S+I+ (IA) the three basic types of antagonistic unidirectional interactions are shown. Parametric structures of synergistic and reciprocal interactions (some examples in Figure 7 and Figure 8) are immediate by symmetry considerations.