Fig. 5

Error convergence rates of the nine different algorithms on the coagulation model. The objective error is the mean over \(\mathcal {T}\)= 25 trials. DOPS, SA, PSO and DOPS-PSO have the steepest drop in error during first 300 function evaluations. Thereafter the error drop in DDS and SA remains nearly constant whereas DOPS continues to drops further. In the alloted budget of function evaluations ESS produces a modest reduction in error. At the end of 4000 function evaluations DOPS attains the lowest error