start:hype_tutorials:automatic_calibration
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start:hype_tutorials:automatic_calibration [2018/09/06 15:14] cpers [Differential Evolution Markov Chain method (task DE)] |
start:hype_tutorials:automatic_calibration [2018/09/06 15:24] cpers [Differential Evolution Markov Chain method (task DE)] |
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| * The derivation of a new parameter set to be tested (the mutation) is also governed by the code ''DEMC_sigma''. "Sigma" and the parameter precision determines how much a random perturbation will influence the new parameter set. "Sigma" is the base of the perturbation. The value is the standard deviation of the sample error. Set to 0 if you don’t want to use it. Default is 0.1. The sigma value is multiplied with 3rd-row value for each parameter (the precision) to determine the size of the random perturbation. | * The derivation of a new parameter set to be tested (the mutation) is also governed by the code ''DEMC_sigma''. "Sigma" and the parameter precision determines how much a random perturbation will influence the new parameter set. "Sigma" is the base of the perturbation. The value is the standard deviation of the sample error. Set to 0 if you don’t want to use it. Default is 0.1. The sigma value is multiplied with 3rd-row value for each parameter (the precision) to determine the size of the random perturbation. | ||
| * The probability to use the new parameter set is governed by the code ''DEMC_crossover'', which is the probability to not use the mutated parameter values. Use 1 to always test the mutation (default), or < 1 to cross over some parameter values from parent generation (recommended if you have large number of parameters). In the example of [[start:hype_file_reference:optpar.txt|optpar.txt]] file shown in Fig 7, the 9th line indicates that the user wants 40% probability to keep the previous/parent parameter set and not to use the mutation. | * The probability to use the new parameter set is governed by the code ''DEMC_crossover'', which is the probability to not use the mutated parameter values. Use 1 to always test the mutation (default), or < 1 to cross over some parameter values from parent generation (recommended if you have large number of parameters). In the example of [[start:hype_file_reference:optpar.txt|optpar.txt]] file shown in Fig 7, the 9th line indicates that the user wants 40% probability to keep the previous/parent parameter set and not to use the mutation. | ||
| - | * As default, only new parameter sets with better optimization criterion is accepted for the next generation. The code ''DEMC_accprob'' is used to switch on the possibility to accept also less good parameter sets. If used, a proposed parameter set is accepted with increasing probability the better its performance is compared to the best parameter set so far. Set to 1 will maximize the probability to accept a proposal, set to 0 to only accept proposals with better performance than the parent generation (default). In the example of [[start:hype_file_reference:optpar.txt|optpar.txt]] file shown in Fig 7, the 10th line indicates that the user wants new generations to be better. | + | * As default, only new parameter sets with better optimization criterion is accepted for the next generation. The code ''DEMC_accprob'' is used to switch on the possibility to accept also less good parameter sets. If used, a proposed parameter set is accepted with increasing probability the better its performance is compared to the best parameter set so far. Set to 0 to only accept proposals with better performance than the parent generation (default), set to 1 to turn on the probability to accept worse proposals. In the example of [[start:hype_file_reference:optpar.txt|optpar.txt]] file shown in Fig 7, the 10th line indicates that the user wants new generations to be better. |
| The specification of calibration parameters start on line 22 in [[start:hype_file_reference:optpar.txt|optpar.txt]]. Listing of the model parameters subject to optimization is achieved as described [[start:hype_tutorials:automatic_calibration#specification_of_calibration_parameters_-_optpartxt|above]]. The model parameters are listed in no particular order, but with three rows for each parameter. The precisions specified in the parameter listing part are used by the DEMC method to scale the random perturbation of the generation of a new proposed parameter set. | The specification of calibration parameters start on line 22 in [[start:hype_file_reference:optpar.txt|optpar.txt]]. Listing of the model parameters subject to optimization is achieved as described [[start:hype_tutorials:automatic_calibration#specification_of_calibration_parameters_-_optpartxt|above]]. The model parameters are listed in no particular order, but with three rows for each parameter. The precisions specified in the parameter listing part are used by the DEMC method to scale the random perturbation of the generation of a new proposed parameter set. | ||
start/hype_tutorials/automatic_calibration.txt · Last modified: 2024/01/25 11:37 (external edit)
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