## Fitting of Kinetic Tissue Models

As soon as a kinetic model has been selected a model curve is calculated and shown in the curve display. The model curve represents the activity concentration values PET would measure if the model correctly described the observed physical processes. Fitting assumes that the model configuration is adequate and tries to find the set of model parameters for which the model curve is in optimal agreement with the measurement.

The following sections explain how a model is configured, fitted to data, and assessed for goodness-of-fit.