Experience shows that the cost of producing one chocolate bar varies between 20 and 40 cents with 30 cents as the most likely cost. The total production cost is of course the product of the number of chocolate bars we produce and the cost pr bar. Now, the question is: Where do we enter the cost pr. bar? There are two possibilities: The perhaps most obvious thing would be to add another node and call it something like 窶弃roduction cost pr. bar窶. We could then add an edge from this new node to the 窶弃roduction cost窶 node. A more compact solution would be to hide the 窶弃roduction cost pr. bar窶 inside the 窶弃roduction cost窶 node as a 窶徑ocal value窶. The actual output value of the node should combine this local value with the input from the 窶廸umber of chocolate bars窶 node. Since we do not care so much about the 窶弃roduction cost pr. bar窶, we will use this approach here.
Double-click on the 窶弃roduction cost窶 node.
In the 窶廬dentity窶 view, enter 窶$窶 in the 窶弑nit窶 field, and then go to the 窶廛istribution窶 view.
Select the 窶廸ormal窶 distribution, and enter the following numbers in the parameter fields:
a) 0.2
b) 0.3
b) 0.4
Note that in this case we just use 1 in the 窶廰.Fact.窶 field, and insert the actual fractiles directly into the (a), (b) and (c) fields. Thus, we are using the absolute uncertainty approach in this case. Make sure the 窶廬nclude stochastic value窶 checkbox is checked.
