Error Propagation (uncertainty) |
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This module is useful when exploring statistical behavior of a variable which is not measured but computed from measured variables or from variables with a known statistical behavior. Using the module, range of the resulting variable, its mean and confidence interval can be estimated. The individual measured variables contributions to the resulting variable variability can be determined as well. The approach is sometimes called uncertainity evaluation or error propagation. Resulting variable properties are evaluated by the Monte Carlo simulation and by the second order Taylor expansion.
Simulation - Pdf manual
Example
Data:
AP |
3.488 |
3.328 |
3.298 |
3.493 |
3.353 |
.... |
Text Output:
Error Propagation, Uncertainty |
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Task name : |
Sheet1 |
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Function : |
(X1-X2)*ln(Y1) |
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No. of simulations : |
1000 |
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Input variables : |
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Mean |
Std. deviation |
95% interval |
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X1 : |
40 |
4 |
32.16 |
47.84 |
X2 : |
50 |
10 |
30.4.2007 |
69.6 |
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Input data : |
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Mean |
Std. deviation |
95% interval |
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Y1 : |
4.851617133 |
1.406598457 |
2.094684157 |
7.608550109 |
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Output value : |
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Median : |
-14.71772521 |
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Mean |
Std. deviation |
95% interval |
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+-3sigma |
-15.38768532 |
17.20265039 |
-49.10488009 |
18.32950945 |
-66.9956365 |
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Interval of generated values |
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-51.98832859 |
17.66283193 |
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Sensitivity analysis |
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Absolute sensitivity : |
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x1: |
1.711697033 |
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x2: |
1.711697033 |
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y1: |
1.805592704 |
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Relative sensitivity : |
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x1: |
26.8396 |
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x2: |
67.099 |
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y1: |
15.92717428 |
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Taylor expansion approximation |
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Simple mean : |
-15.79312079 |
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Corrected mean : |
-15.37284183 |
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Corrected mean (w/covar.) : |
-15.37284183 |
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Corrected std. deviation : |
17.25502425 |
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Corr. std. dev. (w/covar.) : |
17.25502425 |
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95% interval : |
-49.19268936 |
18.44700569 |
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Interval +-3sigma : |
-67.13791457 |
36.3922309 |
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Graphical Output:
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