Tornado Sensitivity Plot Limitations

[kevybear]

Currently, the tornado plot for sensitivity ranks parameters based on output sensitivity. It chooses low, base, and high values for each parameter selected and the low/high values are calculated based on a sensitivity input parameter (variation %). For example, if user inputs 20% as variation then the low value is 80% of the baseline value.

The problem is that some parameters don't vary linearly or inversely with the output so for example, the output at the baseline value may be lower than both the outputs at the low and high values (imagine a parabola with a minimum at the baseline value). In this case there is no way to display the higher order relationship.

Right now it finds the high and low value and fills in the space with a color gradient.

Possible solutions:

• Calculate at more intervals other than low, base, high values and somehow report all of that.
• Instead of calculating the variation in both direction, let the user specify +20% or -20% from baseline values -- will look like this:
  One sided tornado diagram