Levels of measurement and roles

As was mentioned previously, the Types tab is the most important tab within any source node. Let's take a closer look at the Types tab:

1. Edit the Var. File node.
2. Click on the Types tab.

The Field column displays each field's name. The Measurement column determines how Modeler will use each field. Initially, fields with numeric values are typed as Continuous, and fields with string values are typed as Categorical. It is important to make sure that when you are initially reading in data, you only have fields with the measurement levels Continuous or Categorical, if this is not the case, you can manually change this.

The current display is based on 50 lines of data and thus presents partially instantiated measurement levels. Measurement levels are fully instantiated when all data passes through the node.

Instantiation refers to the process of reading or specifying information, such as the measurement level and values for a field:

To instantiate the data:

1. Click Read Values...