Figure 4.

Contours of the objective function, Φ($\overline{frap}$), in a) D_f - $K_a^{*}$, b) D_f - K_d, c) $K_a^{*}$ - K_d, and d) D_f - $K_a^{*}$ - K_d planes for the synthetic data. The response surfaces were generated using a rectangular grid. The domain of each parameter was discretized into 100 discrete points resulting in 10000 grid points for each response surface plot.