Regularization of the AVO inverse problem by means of a ...
Regularization of the AVO inverse problem by means of a ...
Regularization of the AVO inverse problem by means of a ...
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APPENDIX C<br />
Calculation <strong>of</strong> root mean square error<br />
In this section, <strong>the</strong> calculation <strong>of</strong> root mean square error (RMSE) which is used for <strong>the</strong><br />
Monte Carlo Simulation is given. Let <strong>the</strong> true (t) and <strong>the</strong> inverted (i) parameters are<br />
represented <strong>by</strong> vectors x t j and xi j respectively at <strong>the</strong> jth realization. For N number <strong>of</strong> time<br />
samples, each vector has N number <strong>of</strong> elements. Then <strong>the</strong> root mean square error at <strong>the</strong><br />
j th realization, R j x, is defined as<br />
R j x =<br />
<br />
<br />
<br />
1<br />
N<br />
N<br />
k=1<br />
(x t jk − xi jk )2 . (C.1)<br />
Therefore, for n realizations, <strong>the</strong> root mean square error can be calculated using<br />
¯Rx = 1<br />
n<br />
n<br />
R j x. (C.2)<br />
j=1<br />
The corresponding standard deviation for ¯ Rx is given <strong>by</strong><br />
<br />
<br />
<br />
σx = 1<br />
n<br />
(R<br />
n<br />
j x − ¯ R j x) 2 . (C.3)<br />
j=1<br />
From equations (C.2) and (C.3), we can easily see that<br />
¯Rx − σx < RMSEx < ¯ Rx + σx, (C.4)<br />
Note that this calculation is for n realizations at a specific S/N. The x represents an <strong>AVO</strong><br />
parameter; P-wave reflectivity, S-wave reflectivity or density reflectivity.<br />
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