Stories

A story is a sequence of pages that, typically, display model structure while providing the tools and narrative for the user to understand what the structure means and its implications for behavior. From the user's perspective, a story page is different from a regular interface page only because the keyboard can be used for navigation - space bar or down arrow to advance, and up arrow to go back.

A good story is engaging and suspenseful, just like its namesake. There are several ways to accomplish this, but a hook that makes the user want to know the answer to a question, or see how a conflict resolves, can be very effective.

To create a story

Click on Add a new story on the dropdown at the top of the Pages Panel (Interface), and the Create Story dialog will open. Select a story name, and the module that you want to display the content of. The Setup visibility dialog will open on that module, and you can select which (if any) variables should be present on the first page of the story. See Building a Simple Interface for strategies to keep the model visible as the story unfolds. See the Model View object discussion for details on changing the visible content on a page (every story page uses a model view as the background).

To add pages to a story

Either create a new story, or select an existing story from the dropdown at the top of the Pages Panel (Interface). Then, click on the thumbnail of the page that you want to add the new page after, and click on the Add Page button at the bottom of the panel. The Setup visibility dialog will open with the selection set for the current page. Change the variables and connectors selected. You'll typically add more as the story progresses.

To delete a page from a story

Click on the thumbnail of the page you want to delete, and click on the Delete Page button at the bottom of the panel.

To add objects to a story page

A story page is the same as any interface page, and you can add any controls to it you choose. However, since story pages are sequential, using Templates can dramatically simplify the story creation process. You can use a single template for all pages in the story, or different templates for different pages (and don't forget that templates can themselves include other templates).

To enter a story

Use a Button (Interface) and select the command action Navigate to Story. Most commonly, you'll start at the first page of a story, but you can navigate to any page within the story.

To exit a story

Add a Button (Interface) with an action to Navigate to Page, and select the page you want to navigate to. You can also navigate to another story.

To simulate visible structure

Add a button with the action Run, Simulate, or Advance. Only the visible structure will simulate (though all model variables will be initialized). If a converter is not shown, its initial value will be used when computing any visible variables. If a flow is not shown, it will be treated as 0 for any stocks it connects to (the stocks will not change) but its initial value will be used in any equations it is used in. If a connector isn't shown, the equation of the variable the connector points into will simulate using the initial value of the variable the connector comes out of.

You can also start Stella Live in storytelling - only the visible model structure will be part of the resulting simulation. You can start and stop Stella live on a page, or start it and leave it active throughout the story.

If your model includes modules, and you have specified Run by Module in the Partial Simulation Setup portion of the Properties Panel, then when you make a module visible it (and all the modules it contains) will simulate. This can be an effective way to show policy impacts without showing the detail of the policy. See Running Modules for more discussion.

Note The connectors into and out of modules do not affect simulation results. It is only the visibility of the module that matters.