Regions
The Regions page is the interface for determining the geographic Regions to be used in the TREDIS analysis, as well as for managing Regional Definitions to be used and re-used across projects.
Geographic Units in TREDIS
A TREDIS license is associated with specific counties, defined when the license is set up. Additionally, a license may have access to custom geographies, usually subcounty areas, if your license is set up to provide them. In any case, these are the basic building blocks used to build economic regional models, and each geography has its own detailed economic data, with metrics for hundreds of individual economic sectors.
Whether county-based or subcounty-based geographies are being used, they can be combined to form a Region in TREDIS. This is the smallest unit of geography for a TREDIS analysis, and any results reported by geographic area will be reported on by Region.
There are many reasons you might group smaller geographies into Regions. The following use cases represent some of the most common examples.
- You are interested in seeing the impacts of road improvements across the state, so you select all the counties in the state to make a single Region.
- You want to know the impact of bridge investments within the counties of a single MPO, but you also want to know if there are secondary economic impacts on the rest of the state. You create one Region with all the counties in the MPO, and another Region labeled "Rest of State" for all the other counties in the state.
- You want to know the impacts of a rural transit system on a single county, and you don't have any reason to look into impacts outside of that county. You select the county by itself to create a single Region.
A project must have a minimum of one Region, and each Region must be comprised of at least one geography (that is, at least one county or sub-county area). No two Regions may share the same geography, because allowing them to would mean you might inadvertantly double-count any impacts or benefits associated with a single county or sub-county area.
Using the Interface
To define and build the economic model you'll need for a TREDIS analysis, complete the following steps.
Defining Regions
Aside from the default single Region that is provided whenever you create a project, you can add other regions with the Add Region button at top left. Each region is represented by a Region tile at the left, and each Region has a distinct color. In the screenshot, there are four Regions created, each colored on the map. Notice that some Regions have multiple counties associated with them, while one, "Worcester," is a single county.
In this example, the Regions have already been defined, and the counties that belong to them have already been selected. To do this in your own project, you can use one of two methods:
- Select the colored bar within the Region tile at left, and click on the map to add a county to the Region.
- Click on the dropdown menu within the Region tile and check boxes to add geographies to the Region.
In the screenshot, the first Region, named "Boston Area," is represented by the color red, and the counties associated with it are colored red on the map.
The last Region tile, for "Plymouth and Cape," has an open dropdown menu where the counties associated with it are already checked off, and other counties can be added.
On each Region tile, you can click the Rename button to relabel it, or Delete to get rid of the Region entirely.
Saving Definitions
Once you are satisfied with the Regions you have defined, confirm your selections by clicking Save. Alternatively, you can click Revert Selection to get rid of any changes since your last save.
After you've saved the current definition, the Save button will appear gray to signify that the current definition is ready to be used to build the economic model. The Build Model button is now highlighted to indicate you are ready to build.
Build the Model
By clicking the Build Model button, you will launch the build process. This may take a few moments and you will see the progress indicator while it is proceeding. Once finished, the regular interface reappears and the button label changes from Build Model to Model Complete.
Reusing Regional Definitions
Regional Definitions may be reused between projects, allowing you to quickly select an existing definition of Regions - one or many - that you've previously stored, without having to click each county in the checkmark lists or on the map. Users may want to store definitions when they will be used frequently, especially across users or in a common business process.
What are Regional Definitions?
The defined Regions that are saved together when you click the Save button constitute a single Regional Definition in TREDIS. The economic model, which is built by TREDIS when you click Build Model, uses the Regional Definition to create the model used.
A single Regional Definition might involve a single region or multiple regions, but there is only one definition associated with any given TREDIS project. Each region may include one or more counties (or custom components such as subcounty areas). Like projects, Regional Definitions are stored at the contract level, so that other users that share a license may access the same Regional Definitions.
Regional Definition Controls
There are three controls with Regional Definitions:
- The Store Current Definition button stores a definition.
- The Select Existing Definition dropdown selects and loads a definition previously stored.
- The Manage Definitions button opens an interface to view and delete stored definitions.
Storing a Definition
Click the Store Current Definition button to make the current Regional Definition available across projects and to other users.
A window prompt will ask you for a name to assign the Regional Definition so it can be referred to later. Once you enter a name and click Create, this Regional Definition will not be available in the Select Existing Definition dropdown to you and other users of your contract.
A Regional Definition must be saved before it can be stored. Storing a definition for later use is different from the effect of the Save button, which just confirms the use of the current definition for the TREDIS project you're currently working on. For an existing project, you will probably have already saved the Regional Definition, and the Save button will be greyed out, as in the figure below. For a new project, you will want to create a Regional Definition as you normally would and click Save. Once you have saved a Regional Definition, click the Store Current Definition button to store it.
Selecting an Existing Definition
For the TREDIS project you are currently working in, if you want to re-use a Regional Definition that has already been created and stored, click on the Select Existing Definition dropdown and select the Regional Definition from the list.
When you select a Regional Definition from the dropdown, TREDIS will prompt you with a warning that whatever the current Regional Definition is - whatever is being shown on-screen currently - will be discarded to load the selected Regional Definition. Select Yes to continue and load the Regional Definition selected.
Managing Definitions
Definitions are stored at the contract level, which means they’re associated with the data year in the contract name. (For example, "TREDIS - 2024" would be for data from 2024.) Other users on the same contract can select and use them. To see all the Regional Definitions associated with the contract, click the Manage Definitions button to open a new window.
To hide definitions (so they don't appear in the Select Existing Definitions dropdown), click the Hide next to the name of the Regional Definition. When you're done changing the status of any Regional Definitions, click Update Hidden. To see definitions that were previously hidden, uncheck the boxes and click Update Hidden. To view the counties (or county equivalents) associated with a Regional Definition, click View on the row of the definition to open a window with that information.
Finally, if you are the creator of a Regional Definition, you may click Delete to do so. A prompt will confirm your choice before the Regional Definition is actually deleted. Other projects using the definition will not be affected analytically, but their Definition will be considered project-specific and unlabeled.