## Link

A link in a Bbn defines a causal arrow from one chance node (discrete or continuous) to another.

In an influence diagram a link can mean one of three things:

1. It can be a causal arrow as in a pure Bbn. This is the case, when the arrow goes from a chance node or decision node to a chance node.
2. It can define the utility function to depend on a chance node or a decision node. This is the case if the arrow goes from a chance node or decision node to a utility node.
3. It can define the order of the decision nodes (See the Decision Node section for more about the order of decision nodes). This is the case if the arrow goes from a chance node or decision node to a decision node.

A link can be established in edit mode by activating the link tool and dragging a line from one node to another.

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