Treatment Analyzer (again)

[megancreutzburg]

I posted this question under the original Treatment Analyzer question but wasn’t sure if you saw it there…

We have two more questions about the treatment analyzer / target analyzer in Path 3.0.4:

When using the Path treatments tab or treatment analyzer, what effect do transition multipliers have? We thought that the transition multipliers would have no effect (i.e., would be overridden by the number of acres specified for the treatments) but when we ran a simple test model to try to treat the same amount of area with the multipliers for each treatment transition either set to 1 or removed from the multipliers list, the results were different.

Also, we are having trouble understanding the budget units. We were under the impression that you could specify a total annual budget, but it sounds like it really just controls the number of scenarios. If this is the case, how is the budget unit field different from the maximum number of scenarios field? How do you specify your overall budget?

Thanks for your help.

[Leonardo Frid]

1.   Multipliers can influence the outcome because the treatment analyzer is just taking a fixed budget and allocating different "transitions targets".  "Transition targets" can interact with multipliers because the multipliers can modify the relative probabilities of transitions within a group or between strata.

 

2.  The "number of budget units" is a bit of a cryptic field.  It really just means by how many pieces you want to divide your budget into.  Here is the description from the user guide:

 

This value represents the number of discrete portions into which the total budget is to be divided when the Analyzer automatically generates new scenarios. For example if the number of budget units is set to 5, and the total target cost in Year 1 is calculated as $10,000, then the Analyzer will divide the total budget (in Year 1) into 5 units of $2000 each. The model will run permutations of transition target scenarios by moving one budget unit from one transition group target to another. The higher the number of budget units specified, the smaller the change in area targets between sceanrios.

 

The number of budget units does not actually influence the number of scenarios, only the number of non-zero transition targets that are set in combination with any constraints set unter treatment analyzer constraints.  If the number of permutations exceeeds the maximum number of scenarios that you specify, the model will not run.  The overall budget is specified using your base transition target scenario as the sum product of cost and area for each transition target that you specify.

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