Sensitivities

Which variable appears to be the most important? 

The significance of a variable for a response can be illustrated with ANOVA (analysis of variance) or GSA/Sobol (global sensitivity analysis), e.g for the response/objective acceleration you may find:

New Plot

• To view a new plot select the plot button on the task bar. A seperate window of LS-OPT Viewer opens up.

LS-OPT Viewer

    ANOVA

1. Restart the LS-OPT Viewer and select under Metamodel the item Sensitivity
2. We can slide to observe the sensitivity of results at each iteration. In this case for Iteration 1.
3. Select  Linear ANOVA in the new window.
4. From Response select acceleration.
5. Sort the variables according to their significance.

→ For the response acceleration the variable thickness is the most important, while the other variables are rather insignificant.

GSA/Sobol

1. We can slide to observe the sensitivity of results at each iteration, in this case for Iteration 1
2. Select  GSA/Sobol in the new window.
3. From Responses select acceleration.
4. The user has the choice to Sort the plot by selecting the checkbox in the setup menu (default).
5. To compare multiple plots for sensitivities of the input variables on the various responses, the user can select the split option at the task bar and repeat the previous steps.

•  The viewer allows the user to select multiple responses for sensitivity analysis to get the influence of the variables on e.g. the whole problem or a load case using the following steps:

6. Create a new plot area similar to step 5. Then select the option Multi.
7. Select the necessary responses, in this case all the responses are selected .

• The plot describes the cumulative plot on a single graph w.r.t. the variables. This is only availabe for GSA, not for ANOVA, since GSA values are normalized.