The following tutorials demonstrate model building, simulation, and interface creation within older versions of our software. Please note that your software may look different, but core concepts could still apply.

**Please use Mozilla Firefox when viewing in MacOS**

Model Building

These tutorials demonstrate how to use STELLA and iThink to construct a simple model of a population constrained by natural resources. Each link will launch a short video that requires Adobe Flash Player to run. For hands-on experience building this model, open STELLA or iThink and follow along.

Tutorial 1: Building Blocks

Learn the basic mechanics of creating a stock and flow diagram and assigning values to model entities.

1. Placing stocks
2. Adding documentation and color
3. Drawing inflows and outflows
4. Viewing equation layer
5. Entering values for stocks and flows

Tutorial 2: Running the Simulation

See how to set the parameters for running a model with run specs and to create graphs and tables for viewing the results.

1. Choosing run specs
2. Creating graph pads
3. Scaling variables
4. Creating table pads
5. Formatting tables

Tutorial 3: Adding Feedback

Learn how to create converters, link model entities with connectors, and display the cause and effect relationship between model elements by assigning polarity to their connection.

1. Placing converters
2. Adding connectors
3. Defining converters
4. Defining graphical functions
5. Defining ghosts
6. Assigning polarity

Tutorial 4: Organizing and Testing

See how sensitivity analysis can be used to test the effect of changing the value of a model variable. Become familiar with sector frames and how they are used to organize and test parts of a model. Learn how to save and reload simulation data using the data manager.

1. Setting up sensitivity analysis
2. Running sensitivity analysis
3. Creating sector frames
4. Running sectors
5. Managing data from model runs

Tutorial 5: Working with Modules

Learn how to create hierarchical models that use modules to piece together common structure.

1. Creating modules
2. Importing module structure
3. Building module structure
4. Defining inputs and outputs
5. Assigning inputs to variables
6. Running modules

Tutorial 6: Importing and Exporting Data

Learn the basic mechanics involved in importing data from and exporting data to Microsoft Excel.

1. Importing data
2. Exporting data
3. Managing import and export links

Interface Creation

These tutorials provide step-by-step instructions for creating an interface to an existing STELLA or iThink model, allowing users to interact with your model by changing model inputs, running the simulation and viewing output. For hands-on experience creating this model interface, download the archived Tutorial Models and follow along using your STELLA or iThink installation.

Tutorial 1: Creating a Home Page

Learn how to use Text Boxes and Buttons to create a Home Page.

1. Set Interface Preferences
2. Add Text Box
3. Add Information Button
4. Add Navigation Buttons
5. Define Navigation (part 1)
6. Define Navigation (part 2)
7. Add Storytelling Button

Tutorial 2: Creating a Simulation Lab

Add interface objects that provide a "laboratory" environment to experiment with the model. Let users modify model inputs, run simulations and view results with Graphs, Menu Buttons, Numerical Displays, Status Indicators, Sliders, and Switches.

1. Add Graph Pad
2. Add Menu Buttons
3. Change Simulation Speed
4. Add Numeric Display
5. Add Status indicator
6. Add Sliders
7. Add Switch

Tutorial 3: Create Assumptions Page

Add Knobs and Graphical Input Devices to your interface allowing users to change initial values or assumptions about the relationships defined in your model. See how Graphics Frames can make your interface more visually appealing to users.

1. Copy Navigation Button
2. Add Knobs
3. Add Graphical Input Device
4. Add Graphics Frame

Tutorial 4: Storytelling

Storytelling is an effective way of helping others to understand your model. Learn how to build a story for your model.

1. Build Story
2. Annotate Story
3. Rehearse Story

Other Tutorials

These tutorials demonstrate how to use specific features in the STELLA and iThink software. Each link will launch a short video that requires Adobe Flash Player to run. We're adding to this library based on your feedback, so please send us your ideas.

Conveyors

Learn when and how to use discrete Conveyor stocks.

1. Using Conveyors
2. Conveyors with Leakage
3. Varying Transit Time