Crystal Ball offers an initial sensitivity analysis tool to Tornado charts are a great way to identify important input distributions for further inspection. Spider charts are a great option to further measure the influence that key input variables have on the output (aka "oneatatime perturbation"). We recommend that after this analysis, you will however perform a second sensitivity analysis. The initial sensitivity analysis proceeds as follows to generate a Tornado Chart and Spider Plot:
, as they not only show the effect of each extreme of the input variable, but also reveal nonlinearities between model inputs and outputs. Below we explain how spider charts work with different simulation software:
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Advanced sensitivity analysis proceeds as follows:
@RISK then:
Once all inputs have been treated this way, we get a spider plot such as the one below: Often this type of plot has several horizontal lines for variables that have almost no influence on the output. It makes the graph a lot clearer to delete these. Now we can very clearly see how the output mean is influenced by each input. The vertical range produced by the "Success" variable shows the range of Net Present Value there would be if the project succeeded or not (ranging from $3.5M losses to $4M gains). The next largest range is for the sales volume, etc. The analysis helps us understand the degree of sensitivity in terms we understand (in this example, predicted monetary gains/losses) rather than correlation coefficients that other sensitivity analysis techniques use. 
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Crystal Ball can create spider plots and tornado charts changing one variable at a time, using the following steps:

Crystal Ball then:

Once all inputs have been treated this way, we can plot the following Spider Plot: 
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Often this type of plot has several horizontal lines for variables that have almost no influence on the output. It makes the graph a lot clearer to delete these. 
Now we can very clearly see how the output mean is influenced by each input. The vertical range produced by the Sales price line shows the range of expected profits there would be if the Marketing costs was fixed somewhere between the minimum and maximum (a range of $5,000). The next largest range is for the Distribution costs ($3500), etc. The analysis helps us understand the degree of sensitivity in terms we understand rather than correlation coefficients that other sensitivity analysis techniques use. 
The Tornado Chart Tool can also plot a Tornado chart (also using the "Tornado Chart Tool" in Crystal Ball). The numbers on the left and right of the bars represent the most extreme percentile results. 
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Caveats: 
There are several caveats of using this initial sensitivity analysis with the Tornado Chart Tool of Crystal Ball:

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Better ways:
First, Crystal Ball offers another sensitivity analysis, that provides you with the ability to rank the assumptions according to their importance to each forecast cell. At Epix Analytics, we prefer this method above the one displayed above.
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Differences with @RISK: The steps taken in 
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@RISK advanced sensitivity analysis are fairly similar to 
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those described above, but instead of calculating the forecast, the forecast values are simulated and the 
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analyst can chose what statistic (e.g. the mean) will be reported. Because in this analysis the results are simulated, correlations and other dependency relationships are taken into account, making it a more robust option. 