The Pareto Controls pane is on the PEST Properties dialog box under Pareto.
The variables specified on the Pareto Controls pane are described in the PEST User Manual, Part I, Section 13.2.2. More extensive descriptions of these variables are in the PEST user manual. The variables specified on this pane appear in the Pareto section of the PEST control file.
PARETO_OBSGROUP is the name of an observation group cited in the PEST control file. This group must possess at least one observation of non-zero weight. PEST applies a changing multiplier to the weights associated with all observations belonging to this group as a means of exploring the Pareto front. The objective function component associated with this observation group thus becomes one of the two objective function components (the prediction objective function component) in the trade-off which defines the Pareto front. The other objective function component involved in definition of the Pareto front (the calibration component) is the sum of all contributions made to the objective function by all other observation groups featured in the PEST control file.
PARETO_WTFAC_START is the initial weight factor that PEST should apply to members or the observation group PARETO_OBSGROUP (i.e. the predictive observation group). This defines the point at which PEST commences its journey along the Pareto front. In many contexts PARETO_WTFAC_START will be zero, this dictating that the journey commences at one extreme of the front, this being the calibration end of the front.
PARETO_WTFAC_FIN is the final weight factor that PEST must apply to the PARETO_OBSGROUP observation group. Some experimentation may be required to determine a suitable value for this variable. If, however, the user has provided a weight (in the PEST control file) to the single member (or multiple members) of this group which defines the maximum amount that he/she would like the hypothesized prediction to find expression in the total objective function, then a suitable value for PARETO_WTFAC_FIN may be 1.0. However there is no reason why PARETO_WTFAC_FIN cannot be greater than 1.0; indeed an initial Pareto run may determine that it needs to be thus.
NUM_WTFAC_INC is the number of increments by which PEST should vary the weight factor in raising it from PARETO_WTFAC_START to PARETO_WTFAC_FIN.
NUM_ITER_START, NUM_ITER_GEN, and NUM_ITER_FIN These variables dictate how many optimisation iterations PEST should devote to minimising the total objective function (i.e. calibration plus prediction objective functions) based on each prediction weight factor that it employs in its journey along the Pareto front. NUM_ITER_START pertains to the first weight factor used (namely PARETO_WTFAC_START); NUM_ITER_START can be zero or greater. NUM_ITER_FIN pertains to the final predictive weight factor used (namely PARETO_WTFAC_FIN); this can also be zero or greater. NUM_ITER_GEN is employed for weight factors in between. This must be one or greater.
OBS_REPORT_(N) PEST can write the value of selected observations for each iteration as it traverses the Pareto front. It writes the values to the binary .ppd file generated when PEST runs in Pareto mode. The PEST utility PPD2ASC can be used to convert the .ppd file to a text file.
