Reaction {rdecision}

A reaction (chance) edge in a decision tree

Description

An R6 class representing a reaction (chance) edge in a decision tree.

Details

A specialism of class Arrow which is used in a decision tree to represent edges whose source nodes are ChanceNodes.

Super classes

rdecision::Edge -> rdecision::Arrow -> Reaction

Methods

Public methods

• Reaction$new()

• Reaction$modvars()

• Reaction$set_probability()

• Reaction$p()

• Reaction$set_cost()

• Reaction$cost()

• Reaction$set_benefit()

• Reaction$benefit()

• Reaction$clone()

Inherited methods

• rdecision::Edge$endpoints()
• rdecision::Edge$is_same_edge()
• rdecision::Edge$label()
• rdecision::Arrow$source()
• rdecision::Arrow$target()

Method new()

Create an object of type Reaction. A probability must be assigned to the edge. Optionally, a cost and a benefit may be associated with traversing the edge. A pay-off (benefit-cost) is sometimes used in edges of decision trees; the parametrization used here is more general.

Usage

Reaction$new(source_node, target_node, p, cost = 0, benefit = 0, label = "")

Arguments

source_node

Chance node from which the reaction leaves.

target_node

Node which the reaction enters.

p

Conditional probability of traversing the reaction edge.

cost

Cost associated with traversal of this edge (numeric or ModVar).

benefit

Benefit associated with traversal of the edge (numeric or ModVar).

label

Character string containing the reaction label.

Returns

A new Reaction object.

Method modvars()

Find all the model variables of type ModVar that have been specified as values associated with this Action. Includes operands of these ModVars, if they are expressions.

Usage

Reaction$modvars()

Returns

A list of ModVars.

Method set_probability()

Set the probability associated with the reaction edge.

Usage

Reaction$set_probability(p)

Arguments

p

Conditional probability of traversing the reaction edge. Of type numeric or ModVar. If numeric, p must be in the range [0,1].

Returns

Updated Reaction object.

Method p()

Return the current value of the edge probability, i.e. the conditional' probability of traversing the edge.

Usage

Reaction$p()

Returns

Numeric value in range [0,1].

Method set_cost()

Set the cost associated with the reaction edge.

Usage

Reaction$set_cost(c = 0)

Arguments

c

Cost associated with traversing the reaction edge. Of type numeric or ModVar.

Returns

Updated Reaction object.

Method cost()

Return the cost associated with traversing the edge.

Usage

Reaction$cost()

Returns

Cost.

Method set_benefit()

Set the benefit associated with the reaction edge.

Usage

Reaction$set_benefit(b = 0)

Arguments

b

Benefit associated with traversing the reaction edge. Of type numeric or ModVar.

Returns

Updated Action object.

Method benefit()

Return the benefit associated with traversing the edge.

Usage

Reaction$benefit()

Returns

Benefit.

Method clone()

The objects of this class are cloneable with this method.

Usage

Reaction$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

Author(s)

Andrew J. Sims [e-mail]