Decision Threshold with a Profit Matrix

[pvareschi]

In "Lesson 7: Model Assessment Using SAS Enterprise Miner" (of Module 3), topic "Calculating Expected Profit" seems to imply that using a Profit Matrix results in Enterprise Miner calculating a new threshold for making a prediction decision (text from the online lesson: "When the elements of the profit consequence matrix are constants, SAS Enterprise Miner makes prediction decisions solely based on the estimated probability of response and a constant decision threshold")

However, based on some tests I have done with Decision Trees, from displaying the maximal tree and looking at field "Predicted Value" in each node (as displayed on the Tree window), it looks to me that the classification of a node (i.e. the assignment to either 1 or 0) is solely based on the posterior probabilities (adjusted for prior probabilities - if specified) and the default cut-off of 0.50.

Said in other words, the definition of a Profit Matrix does not change the way nodes/leaves are classified, but it only affects the selection of the best sub-tree which is done based on metric Average Profit; such optimisation is carried out only if property Assessment Measure is set to "Decision" (and, of course, Method = Assessment).

Is my understanding correct?

[Cynthia_sas]

Hi:
We've asked the course instructors for their feedback.
Cynthia