An alias node is a visible reference to a regular node, called the “ego node” of the alias. You can recognize alias nodes by the small arrow in the upper left corner of its icon.

Most of the properties of an alias node actually “belongs” to its ego. If you make changes to an alias node, you actually edit the corresponding property of its ego. Moreover, the alias node will be updated if changes are made to its “ego node”.

If you double-click on an alias node, the folder containing the “ego node” is opened and the ego node is selected. If you delete an alias node, the ego node is not deleted. However, if you delete the ego node, all its aliases will be deleted too.

The main purpose of alias nodes is to facilitate links between nodes in different folders. Assume e.g., that you have several submodels in different folders, and you want to incorporate results from these submodels into a higher level model. You then create alias nodes for each of the nodes you want to connect and put the alias nodes in a new folder representing the higher level model. The alias nodes may then be incorporated in the higher level model and e.g., a “total result” node for all the submodels may be created.

Aliases can also be used to collect in a single folder visible references to nodes in many other folders. This is useful e.g., if you want to perform a simulation on a large model with lots of submodels, and you want to store simulation results from nodes belonging to different submodels. To do this, you just make aliases of all the nodes you want to store simulation results for, and throw these into a folder. Then you run a simulation from this folder.

Alias nodes are not allowed to have “input edges”. If you want to connect an edge to an alias node, you must connect it to the “ego node” instead. The purpose of this restriction is to make it easier to avoid circular (and hence illegal) relations in the influence diagram model.

Note that in DynRisk, you cannot make aliases of folders.