Node Formulas

Decision trees are a unique type of model in DecisionPro because you don’t have to enter a formula in the Formula Bar. Instead, DecisionPro builds the formulas for you automatically. Despite this fact, there are times when you will want to edit the formulas directly. For example, if you want to change the order in which branches are drawn.

Decision trees contain four node types: decision, event, pass through, and end; each is described below:

Decision Nodes

Decision nodes are constructed using the following formula:

NodeName := IncValue -> max( Option1, Option2 ,... )

For example, the root node in the real estate example looks like this:

Root:=0->max(Buy Property,Do Nothing)

You can have any number of options listed in the max statement. The order in which the options are listed controls the order in which the branches are drawn.

Event Nodes

Event nodes have the following format:

NodeName := IncValue -> emv( P1, Outcome1, P2, Outcome2, ... )

For example, the node Request Rezone is defined as

Request Rezone:=-5000->emv(60%,Approved,40%,Denied)

Arguments in the emv statement are always supplied in pairs. The first argument in the pair is the branch probability and the second argument is the branch name.

Pass Through Nodes

Pass through nodes have the format

NodeName := IncValue -> ( NextNodeName )

For example,

Buy Property:=-200000->(Request Rezone)

End Nodes

End nodes simply contain an incremental value using the syntax

NodeName := IncValue ->

For example,

Sell Property:=250000->