Temporal Indices
Context
- In BayesiaLab, you can assign Temporal Indices to nodes. This allows defining a temporal order between nodes, which is taken into account by the learning algorithms when a network is learned.
- For instance, a learning algorithm would not discover that node A is a parent or ancestor of node B if the Temporal Index of node A is greater than the Temporal Index of node B.
- Temporal Indices can take on any real values equal to or greater than 0.
- A Temporal Index of 0 would refer to the nodes associated with the oldest possible point on a timeline, while higher values indicate that nodes are associated with more recent points on that same timeline.
- However, there is no meaning associated with the interval between individual Temporal Indices. For learning purposes, in the case of two nodes, the Temporal Indices of 0 and 1, respectively, convey exactly the same temporal ordering as the values of 0.2 and 0.3, for example.
- By default, there are no Temporal Indices assigned to nodes.
Usage
There are several ways to edit Temporal Indices:
- Select Node Context Menu > Properties > Temporal Index and specify a value.
- Select Graph Panel Context Menu > Edit Temporal Indices to open the Temporal Indices Editor.
- Click on the Temporal Index indicator in the Status Bar to bring up the Temporal Indices Editor.
Example & Workflow Animation
- For illustration purposes, we use the well-known Visit Asia example. Here, we assign a temporal ordering based on domain knowledge, i.e., demographic variables preexist prior to risk factors, which precede conditions, which come before symptoms.
- Furthermore, we use the Associate Color function in the Temporal Indices Editor and sort the table in ascending order.
Import/Export Temporal Indices
The Import and Export buttons in the Temporal Indices Editor allow you to manage Temporal Indices using Dictionaries.