multiple labels not sees as labels
I understand that a learner (for instance Neural Net) tries to learn the function to get from "regular" attributes to "label" attributes. When I change the role of an attribute from "regular" to "label" and then the next one, the first "label" just disappears. That seems to be normal behavior.
So I created a loop that assigns roles "label1", "label2", etc to my target attributes. That works well and I can see the attributes that are my functions input as "regular" and my target outputs as "labelN" (where N is the number of the label).
So far so good.
But now the Neural Network learner complains that it does not see any "label" attributes in the training set...
I have tried "label_Attribute Name" and "label Attribute Name" and "label_N" but to no avail.
Should the learner not recognize any role that starts with "label" as the target outputs?