The Parameter Estimation node () and related subnodes have the options and settings for the definition of parameter estimation calculations based on the predefined reactor types in the Reaction Engineering interface. Add the node from the Reaction Engineering toolbar or right-click Reaction Engineering and add it from the context menu.

The parameters to be estimated are defined in the Estimation parameters table. The parameter names are entered in the Parameter column. An Initial value is also required for each variable. To connect the estimated parameters to the model, make sure that the same parameter naming is used within the rest of the Reaction Engineering interface.

Bounds for the parameter values are specified in the Lower bound and Upper bound columns of the Estimation parameters table. These are applicable when the SNOPT optimization solver method is used. The default solver method for parameter estimation is Levenberg–Marquardt, which currently does not support parameter bounds. Enter a Scale indicating a typical magnitude of the control variable. The relative solver tolerances refer to variables rescaled with respect to this scale, and it may also influence the search pattern of some optimization solvers.