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Hi Brent,
Here are some answers to your questions:
1. How do you enter fire history information under the Advanced Tab?
a. In the "Scenario Exporer" navigate to the Advanced Tab and the "Transition Multiplier Values" property.
b. Right click on the grid and select "Export All". Save the file to a desired location. and click ok. Excel will open with a blank template for you to enter your transition multiplier data into.
c. For each timestep over the simulation period you want to run and for each wildfire transition type enter the (amount of area burned)/(the average amount of area burned per year across all years). Set the transition multiplier type to "temporal".
d. You may need to calibrate wildfire probabilities up and down using a static transition multiplier as well. Do this by creating a transition multiplier value record for each wild fire type and leaving the timestep and transition multuplier type blank.
e. Import the transition multiplier values by returning to Path and the scenario editor and right clicking on the grid to import the edited excel file.
2. Fire transition groups are no longer used in Version 4 of Path. My recomendation would be to upgrade the version. Otherwise, fire transition groups (abandoned in version 3) are to define which transition groups the legacy fire history property would apply to.
3. Yes you can also add transion multipliers for drought to force higher drought probabilities for specific timesteps.
If you have any questions about this let me know and we can have a closer look at your data.
Regards,
Leonardo
Strata are Project Definitions accessible through the "File | Project Definitions…"menu, not Scenario Properties. They need to be exported/imported individually. Scenario properties are accessible through the "File | Open Scenario" menu or through the context menu in the project explorer.
In version 4 of Path you can do this. Just export the full scenario file and then when you are in the scenario explorer for the individual property you want to import click on the import button and point to the Scenario-1.xlsx file. Path will find the right worksheet based on its name.
See this post http://www.apexrms.com/content/treatment-analyzer-again
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.
Hi Steve,
It looks like you are missing the Microsoft Excel Interop Library. Try getting the install from here:
http://www.microsoft.com/en-us/download/details.aspx?id=3508 for office 2010
http://www.microsoft.com/en-us/download/details.aspx?id=18346 for office 2007
Cheers,
Leonardo
The problem with leading zeros in definitions when exporting and importing properties is now fixed. When exporting to excel we prefix numerical definition names with an appostrophe (‘) so that they are treated as text and the leading zero is not lost.
There was a bug in the display of the Y axis values which is now fixed. For graphs where the maximum y value is less than 100 we display two decimal places so that you can differentiate values when variation on the Y axis in the same graph is small. We also now allow you to set the minimum value of the Y axis to zero for column graphs which was not possibe before.
Your interpretation of how the Treatment Analyzer works is correct. It heuristically explores different allocations of a fixed budget. There is no optimization given a specific objective. I would suggest using an iterative approach where you try the treatment analyzer a few times in a row until you hone in on a treatment combination that works best. In the past I have found that even one iteration can be quite informative about the activities that have the highest return on investment.
Note that in the latest version of Path (4.2) this feature is called the Transition Target Analyzer. Let us know how it works for you!
At the moment there are two ways you could approach this problem:
1. Export your transition group output to excel using the Reports tab of the Results Viewer and calculate the mean over a specified time period that way.
2. Use the Output Options Property to specify that you want interval mean output instead of annual output for transitions. Set your output interval to 700. You will get your mean values for year zero to 700 and for years 700 to 1000. To set this, you need to edit the Advanced | Output Options for the scenario before running it. Note that the graph will display a single point for each interval, representing the mean for the time period leading up to it.
The reason this is happening is that you likeley have very small area values for these graphs and the axes are not showing decimal places. If you are graphing multiple state classes you can either choose to use the same y axis scale for all or have the min y axixs value be zero. To set these options use the right click context menu on the graphs. You can also try graphing only the individual state class that is having this issue and the problem may be resolved. If you send me your database I may be able to diagnose the problem more specifically.
1. Yes the problem is with the leading zeros. To fix this go to the File | Project Definitions | Strata tab and enclose all of your numeric strata names and abbreviations in double quotation marks ("). Then repeat the steps outlined above, beggining with step 5. I’ll see if we can fix this issue and allow leading zeroes for numeric stratum names in the next version of Path.
2. You should manualy delete any blank rows in your initial conditions excel file prior to importing.
There are a number of ways in which this could be done. The simplest would be to copy the scenario that has pathways specified for all 21 models, delete the initial conditions for the 20 you don’t want to run and rename it for the specific stratum that you are running. To do this you can follow these steps:
1. In the project explorer right click on the scenario that has 21 strata (models) and select Copy
2. Right Click on the folder that holds that scenario and select Paste
3. Right click on the copy of the scenraio and select Rename. Rename the scenario to specify the stratum you want to run.
4. Right click on the scenario again and select Open.
5. Navigate to the Initial Conditions tab, right click on the grid and select Export All.
6. Save the excel file on a location of your choice and it when it appears on your task bar open it.
7. Filter for all strata except the one you want to run and delete their initial conditions records. Remove the filter.
8. Save the excel file and note it’s name and location.
9. Return to the Initial Conditions tab in Path for the scenario that you want to sun a single stratum for and right click on the grid again. Select Import and navigate to the excel file you just edited.Open it and when prompted select Overwrite.
10. There will be only initial conditions for the selected stratum only. You can now run this scenario and it will only run your selected model. You can repeat this for any model you want to run individually.
11. A more advanced approach for this would be to create a scanario with only pathways and a scenario with only initial conditions for each of the models you want to run individually. You can then use dependencies to combine each set of initial conditions with your single set of pathways.
Hi Kori,
When the error message identifies the transition type that belongs to more than three groups you can open your VDDT database in Access and run the following query using these steps:
1. After opening Access, on the menu ribbon select Create | Query Design
2. On the Show Table dialog click Close
3. On the Query Tools ribbon select SQL View
4. Paste the following text into the query window:
SELECT ProbabilisticTransitionGroup.Name, Project.Name, ProbabilisticTransitionType.Name FROM Project INNER JOIN (ProbabilisticTransitionType INNER JOIN (ProbabilisticTransitionGroup INNER JOIN ProbTransGroupProbTrans ON ProbabilisticTransitionGroup.ProbabilisticTransitionGroupID = ProbTransGroupProbTrans.ProbabilisticTransitionGroupID) ON ProbabilisticTransitionType.ProbabilisticTransitionTypeID = ProbTransGroupProbTrans.ProbabilisticTransitionTypeID) ON Project.ProjectID = ProbabilisticTransitionType.ProjectID
GROUP BY ProbabilisticTransitionGroup.Name, Project.Name, ProbabilisticTransitionType.Name
HAVING (((ProbabilisticTransitionType.Name)=[Enter TransitionType Name]))
5. On the Query Tools ribbon click Run
6. Enter the transition type name that the error identified (for example: Mixed Fire) and click OK
7. You will see a table that lists all of the groups that the selected transition type belongs to and the projects in which it belongs to those groups. If more than three groups occur in this table you will need to identify for which projects you would like to remove or rename the groups for which this transition type belongs such that the type only belongs to at most, three distinct groups in a single VDDT database prior to import.
At the moment, your proposed approach is the only possible way to specify different size distributions. I can see what you mean about cumbersome. Do you really have 80 different potential size distributions for each management type or could some of the strata be aggregated to have the same size distribution? For example could you take a management type and split it up into a few different size categories like small partial cut applied to strata x, y, z; medium partial cut applied to strata r, s, t; etc…
In future this is a modification we could consider for Path – allowing the size distribution to be specified by stratum.
