According to the suggestion by @damarginal regarding to estimation trend with Kriging metamodel, I added two options to “example/ metamodeling/kriging/uq_Example_Kriging_05_TrussDataSet” as follows:
MetaOpts.Trend.Type = ‘polynomial’;
I achieved 11 betas and 10 thetas.
Beta: [-0.09401 -0.00044 -0.00234 -0.00336 -0.00378 -0.00194 -0.00082 0.00164 0.00860 0.00106 0.00888 ]
theta: [ 7.33454 9.68573 7.06032 9.66927 8.72347 9.29973 9.82737 8.91830 9.11504 7.66206 ].
The betas are substituted in this formula according to Table 1in User_Manual_Kriging:
Y=β0+ β1x1+ β2x2+ β3x3+ β4x4+ β5x5+ β6x6+ β7x7+ β8x8+ β9x9+ β10x10
And then, I selected the first row data of “Examples\ SimpleDataSets\ Truss_Matlab_FEM \ Truss_Experimental_Design.mat” (X data) and used as x1 ,x2,…,x10. The y value in the mentioned equation is very different the Y value in the first row in : Truss_Experimental_Design.mat (Y data). What is the reason for this difference?
It should be mentioned I use:
and then evaluate the metamodel, the Y value is achieved is more accurate.
The aim is to provide the formula by kriging meta-model. Could anyone help me to find my problem?
Thank you in advance for your time.