Assigning Polarity to Connectors

Assigning polarity to connectors in your model lets you visually indicate the cause-and-effect relationship between model variables. Assigning polarity can also make it easier to tell a story about the feedback loops in your model.

A positive/same polarity (+/S) means that when the cause increases, the effect increases; the relationship between the variables goes in the same direction.
A negative/opposite polarity (-/O) means that when the cause increases, the effect decreases; the relationship between variables goes in the opposite direction.

Note You specify whether +/- of S/O is displayed in the Model Settings Properties Panel.

For example, in the following model, when population increases, its effect is to also increase the effect of crowding (note the "+" polarity sign end of the connector). This is a positive polarity. Conversely, as carrying capacity increases, the result is to decrease the effect of crowding, a negative ("-") polarity.

Choose the polarity you want to assign (positive or negative) based on the interaction between the two variables.

To Assign Polarity to Connectors

Right-click the connector's handle, choose Polarity from the menu that appears, and then choose Positive, Negative, or None.
You can also specify whether you want the polarity symbol to appear on the inside or outside of the connector's arc.