Quick Scenario Analysis with Tree

The Quick Scenario Analysis with Tree page can be accessed from the Main Menu by selecting Scenario Analysis and then Quick Scenario Analysis with Tree. Use this feature to develop, review, and edit scenarios in IFs. This feature allows for building and editing a Scenario File (.sce) which loads interventions to be run in the IFs model to produce a Run File (.run), which displays scenario results.

An example of the Quick Scenario Guide page in IFs when first opened.

This page has a number of features and options to create, load, adjust, and run scenarios. These options and features include:

• Continue: Go back to the previous menu or to the Main Menu of IFs.
• Scenario Files:
  • Clear Tree: Clear any interventions currently loaded to the scenario tree.
  • Open: Load any set of saved or preloaded Scenario Files (.sce). Hover over folder names to find and select the desired scenario. The Open drop-down folders reflect those in \IFs\Scenario file path on the current device. The scenare tree will update with the interventions in the chosen scenario file.
  • Name and Save: Open a pop-up to save the scenario currently reflected in the scenario tree. The pop-up includes two fields to enter text into; type the desired scenario file name and folder name in the fields, then click Save or Cancel. The two fields are:
    • File Name: Enter a file name for the created scenario, which will create a scenario file named FileName.sce.
    • Folder Name: Enter a new or already existing folder name to save the scenario file to that location. This folder will show up in \IFs\Scenario\User Defined Scenarios\ on the current device.
  • Export to IFs Standard CSV Format: Save a CSV version of the scenario to the same folder that the currently displayed scenario is stored in. For newly created scenarios, click Name and Save first before clicking this option. CSV versions of scenarios can be easier to manage and understand, as all years and dimensions are aligned in titled columns, unlike Scenario Files (.sce) that are written in comma-separated text format.
  • Export Working File: Download a Scenario File (.sce) of the current scenario tree.
  • Import IFs Standard CSV Format files: Load a scenario that has been saved using the Export to IFs Standard CSV Format in the scenario tree. This requires that a scenario has previously been saved using the IFs standard CSV format and located in a folder within \IFs\Scenario\. Follow the appropriate file path and click on the desired scenario CSV to import.
• Add Scenario Component: Similar to Open from the Scenario Files options. Layer multiple scenario files or interventions by adding components from another scenario once one has loaded.
• Run Scenario: Open the Run page for the current scenario in the scenario tree. Adjust the horizon to the desired end year and click Start Run.
• Delete Selection: When an intervention is displayed on the screen next to the scenario tree from either clicking on a parameter directly in the tree or from the Parameter Search option, click Delete to remove that intervention from the current scenario.
• Set Group or Country: Click Groups to make interventions for particular groups, or Countries for a particular country or countries. The current selection will have a checkmark next to it.
• Annotate Scenario: Click Annotate to open a description of the scenario interventions based on the current Scenario Tree. An annotation is generated by default, which can be edited or supplemented with explanatory or narrative information describing the scenario. To edit the annotation, click in the text box and change or add text as desired. Below the text box click Save to save edits, Clear to remove all text in the annotation, Help to open the corresponding page in the Pardee Wiki, or Exit to return to the Quick Scenario Analysis with Tree.
• Parameter Search: Click Search to open the Parameter Search page to search to find and select specific parameters. The Parameter Search feature is described below.
• Help: Open the corresponding page in the Pardee Wiki.

Parameter Search

Use the Parameter Search feature to search, explore, and choose parameters to adjust for scenario analysis. Use this feature with the Guide to Scenario Analysis in IFs to find the parameters most useful for the intended intervention or scenario goal. Type the desired parameter name in the search bar, then click Search. Click on the parameter, which will bring up a few options described below. Click Load to select this parameter in the scenario tree. Click Help to open the corresponding page in the Pardee Wiki, or Continue to go back to the previous menu or to the Main Menu of IFs.

An example of the Parameter Search option for the total fertility rate multiplier tfrm.

The options, once a parameter is clicked, include: These options are not available for all parameters.

• Define: See a brief definition of the parameter and how it works.
• Block Diagram (Pop-Up): Open a new tab with a wiki page displaying a diagram and text explanation that broadly explains how drivers interact for the area of inquiry (agriculture, economics, etc.).
• Equations (Pop-Up): Open a new tab with a wiki page of the mathematical equations that are used to determine this parameter.

Using the Scenario Tree

The easiest way to create scenario interventions is to use the Guide to Scenario Analysis in IFs along with the Parameter Search option, described above. The Scenario Tree can also be used to find and select a parameter. Click on any of the categories in the Scenario Tree (ex., Technological change. to open sub -categories and eventually to open up a parameter choices box. Once this box appears to the right of the scenario tree with parameter names and descriptions, click on any parameter to reveal a few options shown below.

An example of the scenario tree being used for Technological Change, Energy, and with the QEM parameter selected; shows the options that selecting a parameter will reveal.

The options include: These options are not available for all parameters.

• Select: Choose the parameter in order to load and edit it.
• Drivers: Click to see what variables are affecting the chosen parameter.
• Explain (Pop-Up): Open a new tab with a wiki page displaying a diagram and text explanation that broadly explains how drivers interact for the area of inquiry (agriculture, economics, etc.).
• View Equations (Pop-Up): Open a new tab with a wiki page of the mathematical equations that are used to determine this parameter.
• Define: See a brief definition of the parameter and how it works.

Adjusting Parameters

Once a parameter is chosen by clicking Select, as described above, a drop-down will appear to choose either a particular country or group. Choose the desired country or group by clicking on it. Another drop-down will appear if the parameter has dimensions (e.g., Male, Female, Total), click on the desired dimension choice, and repeat if the parameter has multiple dimension choices. After this, the selected parameter will appear to the right of the tree with its base value or scenario value (if opened within an already made scenario) shown. An example of this screen is shown below.

An example of a parameter selected to adjust on the Quick Scenario Analysis Tree page. Example of the Government expenditures by destination multiplier (Health) parameter for Argentina.

This screen offers a few basic options for adjusting parameters. Adjust the initial parameter value to make interventions using default changes by clicking the bubble for High or Low, or to return to the base, click Base. Alternately, use the slider or enter the desired number into the field above the slider and click Apply. Using this slider or field option will apply that value to the whole time horizon to the year 2150, with an initial shift period based upon the choice from the Shift Years dropdown. In the example, the value is 5.177, and the shift years are 10, so the parameter interpolates from 1 to 5.177 from 2020 to 2030 and then stays at that value for the whole horizon.

For developing high-quality scenarios, full parameter customization is recommended. Click Fully Customize for more options and to load the Change Values screen.

An example of the Fully Customize option for parameter changes. Example of the Government expenditures by destination multiplier (Health) parameter for Argentina.

The Fully Customize option allows more control over parameter behavior. The Information table displays information on parameter value for a given year, and the minimum and maximum values that IFs recommends for intervention. If above or below these, a warning message will appear. Use the Year field in this table to jump to a particular year to view the value or to start an intervention from.

The Change Numerically table is where the changes to a parameter are made. Use the Next Year or Previous Year buttons to change the Year field by one. Once at the desired year to start an intervention shown in the Year field, enter in the Desired Value field the value to change the parameter to, use the Years to Repeat or Interpolate field to set the number of years for the intervention to take place (this includes the current year so to increase the value for the next 10 years, enter 11). Click Change/Repeat to apply the desired value for the number of years entered (for example, an increase to 8 for 61 years from 2090 to 2150, shown above) or click Interpolate to smoothly shift the value over the number of years entered from the current value to the desired value. Continue to use the Change Numerically table until the parameter is adjusted as desired.

To ensure that the parameter is adjusted as desired, hover over the graph on the right side of the page to see the parameter value in any given year. Click Register Change to apply this intervention to the current scenario, Cancel All Changes to clear the current parameter adjustments, Exit to Scenario Tree to return to the scenario tree, or Help to open the corresponding page in the Pardee Wiki.