Syncrosim › Forums › ST-Sim & State-and-Transition Simulation Models › Adding an outbreak › Reply To: Adding an outbreak

Hi Josh,

If your outbreaks are correlated between strata, I think the best you could do is create an external variable for outbreak years (0/1) and define a value for this for every iteration/timestep. This would reduce the number of records you have to define somewhat but not entirely. To do it, here are the steps I would follow:

1. Create an external variable under Project Properties: “Outbreak Year”

2. Create a Distribution Type under Project Properties: “Outbreak Multiplier”

3. Under **Scenario Properties | External Variables**:Define a value for each timestep and iteration that includes the 0 values for non outbreak years and the 1 values for outbreak years.

4. Under **Scenario Properties | Distributions** you would then define two Distribution records for each stratum that specify the “Outbreak Multiplier” when your “Outbreak Year” value is 0 and the other when it is 1. Set the Sampling frequency to “every timestep”.

5. Under **Scenario Properties | Transitions – Multipliers** set your multipliers to come from the “Outbreak Multiplier” **Multiplier Distribution**. Set the Sampling frequency to “every timestep”.

Hope that helps!

Leonardo