by Dr. Tao Li, Dr. Bas Bouman, and Dr. Annie Boling
Calibration and validation are important processes for any simulation model to understand its uncertainties, confidence levels, and limitations. Model calibration is used to fine-tune input parameters for improving the accuracy of simulations. Model validation (evaluation) is used to quantify the uncertainties and confidences of simulations with measured data. These two processes have been conducted for ORYZA2000 since its official release in 2000.
Here is the list of all contributors for the calibration and validation of ORYZA2000.
Experimental data collection and analysis
The ORYZA2000 model is calibrated and evaluated using well-designed, well-implemented, and well-documented pot and field experiments. Experimental details are given in some sample protocols listed below:
Simulation design
Simulation design should correspond to plot and/or field experimental treatments. One simulation is the representative of one treatment of a pot and/or field experiment at the lowest testing factor level. Replicates are not considered in a simulation study.
Model calibration
To use ORYZA2000 to simulate your own experiments, a set of input files needs to be created as explained in Section 7.1 of the book, ORYZA2000: modelling lowland rice (Bouman et al. 2001). Example model data files (Download HERE) can be used as a start. The experimental data file needs to contain the experimental conditions and data as explained in Section 7.2 of Bouman et al. (2001). Users should go through this data file carefully and adapt each parameter to their own experimental conditions.
Model evaluation
Repeated and well-documented comparisons between model simulations and real-world measurements increase one’s confidence in the suitability of a model for a certain purpose. A combination of graphical presentations and statistical measures are being used to evaluate the performance of the model.