public Proposition GetProposition(object owner, IContextLookup globalVars, IDictionary <string, RandomVariable> randomVariables)
{
switch (PropositionType)
{
case PropositionType.RandomVariable:
case PropositionType.Assignment:
RandomVariable randomVar;
if (!randomVariables.TryGetValue(RandomVariable, out randomVar))
{
throw new ApplicationException("Missing variable " + RandomVariable);
}
switch (PropositionType)
{
case PropositionType.RandomVariable:
return((Proposition)randomVar);
case PropositionType.Assignment:
var objValue = Value.EvaluateTyped(owner, globalVars);
return(new AssignmentProposition(randomVar, objValue));
default:
throw new ArgumentOutOfRangeException();
}
case PropositionType.Dysjunctive:
case PropositionType.Conjunctive:
if (Children.Count > 0)
{
Proposition newPropositionInfo = null;
foreach (PropositionInfo assignmentPropositionInfo in Children)
{
var objAssignment = assignmentPropositionInfo.GetProposition(owner, globalVars, randomVariables);
if (newPropositionInfo == null)
{
newPropositionInfo = objAssignment;
}
else
{
if (PropositionType == PropositionType.Conjunctive)
{
newPropositionInfo = new ConjunctiveProposition(newPropositionInfo, objAssignment);
}
else
{
newPropositionInfo = new DisjunctiveProposition(newPropositionInfo, objAssignment);
}
}
}
return(newPropositionInfo);
}
else
{
throw new ArgumentOutOfRangeException();
}
default:
throw new ArgumentOutOfRangeException();
}
}
protected static void demoToothacheCavityCatchModel(IFiniteProbabilityModel model)
{
System.Console.WriteLine("Toothache, Cavity, and Catch Model");
System.Console.WriteLine("----------------------------------");
AssignmentProposition atoothache = new AssignmentProposition(
ExampleRV.TOOTHACHE_RV, true);
AssignmentProposition acavity = new AssignmentProposition(
ExampleRV.CAVITY_RV, true);
AssignmentProposition anotcavity = new AssignmentProposition(
ExampleRV.CAVITY_RV, false);
AssignmentProposition acatch = new AssignmentProposition(
ExampleRV.CATCH_RV, true);
// AIMA3e pg. 485
System.Console.WriteLine("P(cavity) = " + model.prior(acavity));
System.Console.WriteLine("P(cavity | toothache) = "
+ model.posterior(acavity, atoothache));
// AIMA3e pg. 492
DisjunctiveProposition cavityOrToothache = new DisjunctiveProposition(
acavity, atoothache);
System.Console.WriteLine("P(cavity OR toothache) = "
+ model.prior(cavityOrToothache));
// AIMA3e pg. 493
System.Console.WriteLine("P(~cavity | toothache) = "
+ model.posterior(anotcavity, atoothache));
// AIMA3e pg. 493
// P<>(Cavity | toothache) = <0.6, 0.4>
System.Console.WriteLine("P<>(Cavity | toothache) = "
+ model.posteriorDistribution(ExampleRV.CAVITY_RV, atoothache));
// AIMA3e pg. 497
// P<>(Cavity | toothache AND catch) = <0.871, 0.129>
System.Console.WriteLine("P<>(Cavity | toothache AND catch) = "
+ model.posteriorDistribution(ExampleRV.CAVITY_RV, atoothache,
acatch));
}
//
// PROTECTED METHODS
//
protected void test_RollingPairFairDiceModel(IProbabilityModel model)
{
Assert.IsTrue(model.isValid());
// Ensure each dice has 1/6 probability
for (int d = 1; d <= 6; d++)
{
AssignmentProposition ad1 = new AssignmentProposition(
ExampleRV.DICE_1_RV, d);
AssignmentProposition ad2 = new AssignmentProposition(
ExampleRV.DICE_2_RV, d);
Assert.AreEqual(1.0 / 6.0, model.prior(ad1), DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 6.0, model.prior(ad2), DELTA_THRESHOLD);
}
// Ensure each combination is 1/36
for (int d1 = 1; d1 <= 6; d1++)
{
for (int d2 = 1; d2 <= 6; d2++)
{
AssignmentProposition ad1 = new AssignmentProposition(
ExampleRV.DICE_1_RV, d1);
AssignmentProposition ad2 = new AssignmentProposition(
ExampleRV.DICE_2_RV, d2);
ConjunctiveProposition d1AndD2 = new ConjunctiveProposition(
ad1, ad2);
Assert.AreEqual(1.0 / 6.0, model.prior(ad1),
DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 6.0, model.prior(ad2),
DELTA_THRESHOLD);
// pg. 485 AIMA3e
Assert.AreEqual(1.0 / 36.0, model.prior(ad1, ad2),
DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 36.0, model.prior(d1AndD2),
DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 6.0, model.posterior(ad1, ad2),
DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 6.0, model.posterior(ad2, ad1),
DELTA_THRESHOLD);
}
}
// Test Sets of events defined via constraint propositions
IntegerSumProposition total11 = new IntegerSumProposition("Total11",
new FiniteIntegerDomain(11), ExampleRV.DICE_1_RV,
ExampleRV.DICE_2_RV);
Assert.AreEqual(2.0 / 36.0, model.prior(total11), DELTA_THRESHOLD);
EquivalentProposition doubles = new EquivalentProposition("Doubles",
ExampleRV.DICE_1_RV, ExampleRV.DICE_2_RV);
Assert.AreEqual(1.0 / 6.0, model.prior(doubles), DELTA_THRESHOLD);
SubsetProposition evenDice1 = new SubsetProposition("EvenDice1",
new FiniteIntegerDomain(2, 4, 6), ExampleRV.DICE_1_RV);
Assert.AreEqual(0.5, model.prior(evenDice1), DELTA_THRESHOLD);
SubsetProposition oddDice2 = new SubsetProposition("OddDice2",
new FiniteIntegerDomain(1, 3, 5), ExampleRV.DICE_2_RV);
Assert.AreEqual(0.5, model.prior(oddDice2), DELTA_THRESHOLD);
// pg. 485 AIMA3e
AssignmentProposition dice1Is5 = new AssignmentProposition(
ExampleRV.DICE_1_RV, 5);
Assert.AreEqual(1.0 / 6.0, model.posterior(doubles, dice1Is5),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.DICE_1_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.DICE_2_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.DICE_1_RV, ExampleRV.DICE_2_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.DICE_2_RV, ExampleRV.DICE_1_RV),
DELTA_THRESHOLD);
// Test a disjunctive proposition pg.489
// P(a OR b) = P(a) + P(b) - P(a AND b)
// = 1/6 + 1/6 - 1/36
AssignmentProposition dice2Is5 = new AssignmentProposition(
ExampleRV.DICE_2_RV, 5);
DisjunctiveProposition dice1Is5OrDice2Is5 = new DisjunctiveProposition(
dice1Is5, dice2Is5);
Assert.AreEqual(1.0 / 6.0 + 1.0 / 6.0 - 1.0 / 36.0,
model.prior(dice1Is5OrDice2Is5), DELTA_THRESHOLD);
}
protected void test_ToothacheCavityCatchModel(IProbabilityModel model)
{
Assert.IsTrue(model.isValid());
AssignmentProposition atoothache = new AssignmentProposition(
ExampleRV.TOOTHACHE_RV, true);
AssignmentProposition anottoothache = new AssignmentProposition(
ExampleRV.TOOTHACHE_RV, false);
AssignmentProposition acavity = new AssignmentProposition(
ExampleRV.CAVITY_RV, true);
AssignmentProposition anotcavity = new AssignmentProposition(
ExampleRV.CAVITY_RV, false);
AssignmentProposition acatch = new AssignmentProposition(
ExampleRV.CATCH_RV, true);
AssignmentProposition anotcatch = new AssignmentProposition(
ExampleRV.CATCH_RV, false);
// AIMA3e pg. 485
Assert.AreEqual(0.2, model.prior(acavity), DELTA_THRESHOLD);
Assert.AreEqual(0.6, model.posterior(acavity, atoothache),
DELTA_THRESHOLD);
ConjunctiveProposition toothacheAndNotCavity = new ConjunctiveProposition(
atoothache, anotcavity);
Assert.AreEqual(0.0,
model.posterior(acavity, toothacheAndNotCavity),
DELTA_THRESHOLD);
Assert.AreEqual(0.0,
model.posterior(acavity, atoothache, anotcavity),
DELTA_THRESHOLD);
// AIMA3e pg. 492
DisjunctiveProposition cavityOrToothache = new DisjunctiveProposition(
acavity, atoothache);
Assert.AreEqual(0.28, model.prior(cavityOrToothache),
DELTA_THRESHOLD);
// AIMA3e pg. 493
Assert.AreEqual(0.4, model.posterior(anotcavity, atoothache),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.TOOTHACHE_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.CAVITY_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.CATCH_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.TOOTHACHE_RV, ExampleRV.CAVITY_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.TOOTHACHE_RV, ExampleRV.CATCH_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.posterior(ExampleRV.TOOTHACHE_RV,
ExampleRV.CAVITY_RV, ExampleRV.CATCH_RV), DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.CAVITY_RV, ExampleRV.TOOTHACHE_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.CAVITY_RV, ExampleRV.CATCH_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.posterior(ExampleRV.CAVITY_RV,
ExampleRV.TOOTHACHE_RV, ExampleRV.CATCH_RV), DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.CATCH_RV, ExampleRV.CAVITY_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.CATCH_RV, ExampleRV.TOOTHACHE_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.posterior(ExampleRV.CATCH_RV,
ExampleRV.CAVITY_RV, ExampleRV.TOOTHACHE_RV), DELTA_THRESHOLD);
// AIMA3e pg. 495 - Bayes' Rule
// P(b|a) = P(a|b)P(b)/P(a)
Assert.AreEqual(model.posterior(acavity, atoothache),
(model.posterior(atoothache, acavity) * model.prior(acavity))
/ model.prior(atoothache), DELTA_THRESHOLD);
Assert.AreEqual(
model.posterior(acavity, anottoothache),
(model.posterior(anottoothache, acavity) * model.prior(acavity))
/ model.prior(anottoothache), DELTA_THRESHOLD);
Assert.AreEqual(
model.posterior(anotcavity, atoothache),
(model.posterior(atoothache, anotcavity) * model
.prior(anotcavity)) / model.prior(atoothache),
DELTA_THRESHOLD);
Assert.AreEqual(
model.posterior(anotcavity, anottoothache),
(model.posterior(anottoothache, anotcavity) * model
.prior(anotcavity)) / model.prior(anottoothache),
DELTA_THRESHOLD);
//
Assert.AreEqual(model.posterior(acavity, acatch),
(model.posterior(acatch, acavity) * model.prior(acavity))
/ model.prior(acatch), DELTA_THRESHOLD);
Assert.AreEqual(model.posterior(acavity, anotcatch),
(model.posterior(anotcatch, acavity) * model.prior(acavity))
/ model.prior(anotcatch), DELTA_THRESHOLD);
Assert.AreEqual(model.posterior(anotcavity, acatch),
(model.posterior(acatch, anotcavity) * model.prior(anotcavity))
/ model.prior(acatch), DELTA_THRESHOLD);
Assert.AreEqual(
model.posterior(anotcavity, anotcatch),
(model.posterior(anotcatch, anotcavity) * model
.prior(anotcavity)) / model.prior(anotcatch),
DELTA_THRESHOLD);
}
public void test_RollingPairFairDiceModel(ProbabilityModel model)
{
Assert.IsTrue(model.isValid());
// Ensure each dice has 1/6 probability
for (int d = 1; d <= 6; d++)
{
AssignmentProposition ad1 = new AssignmentProposition(
ExampleRV.DICE_1_RV, d);
AssignmentProposition ad2 = new AssignmentProposition(
ExampleRV.DICE_2_RV, d);
Assert.AreEqual(1.0 / 6.0, model.prior(ad1), DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 6.0, model.prior(ad2), DELTA_THRESHOLD);
}
// Ensure each combination is 1/36
for (int d1 = 1; d1 <= 6; d1++)
{
for (int d2 = 1; d2 <= 6; d2++)
{
AssignmentProposition ad1 = new AssignmentProposition(
ExampleRV.DICE_1_RV, d1);
AssignmentProposition ad2 = new AssignmentProposition(
ExampleRV.DICE_2_RV, d2);
ConjunctiveProposition d1AndD2 = new ConjunctiveProposition(
ad1, ad2);
Assert.AreEqual(1.0 / 6.0, model.prior(ad1),
DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 6.0, model.prior(ad2),
DELTA_THRESHOLD);
// pg. 485 AIMA3e
Assert.AreEqual(1.0 / 36.0, model.prior(ad1, ad2),
DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 36.0, model.prior(d1AndD2),
DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 6.0, model.posterior(ad1, ad2),
DELTA_THRESHOLD);
Assert.AreEqual(1.0 / 6.0, model.posterior(ad2, ad1),
DELTA_THRESHOLD);
}
}
// Test Sets of events defined via constraint propositions
IntegerSumProposition total11 = new IntegerSumProposition("Total11",
new FiniteIntegerDomain(11), ExampleRV.DICE_1_RV,
ExampleRV.DICE_2_RV);
Assert.AreEqual(2.0 / 36.0, model.prior(total11), DELTA_THRESHOLD);
EquivalentProposition doubles = new EquivalentProposition("Doubles",
ExampleRV.DICE_1_RV, ExampleRV.DICE_2_RV);
Assert.AreEqual(1.0 / 6.0, model.prior(doubles), DELTA_THRESHOLD);
SubsetProposition evenDice1 = new SubsetProposition("EvenDice1",
new FiniteIntegerDomain(2, 4, 6), ExampleRV.DICE_1_RV);
Assert.AreEqual(0.5, model.prior(evenDice1), DELTA_THRESHOLD);
SubsetProposition oddDice2 = new SubsetProposition("OddDice2",
new FiniteIntegerDomain(1, 3, 5), ExampleRV.DICE_2_RV);
Assert.AreEqual(0.5, model.prior(oddDice2), DELTA_THRESHOLD);
// pg. 485 AIMA3e
AssignmentProposition dice1Is5 = new AssignmentProposition(
ExampleRV.DICE_1_RV, 5);
Assert.AreEqual(1.0 / 6.0, model.posterior(doubles, dice1Is5),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.DICE_1_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.DICE_2_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.DICE_1_RV, ExampleRV.DICE_2_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.DICE_2_RV, ExampleRV.DICE_1_RV),
DELTA_THRESHOLD);
// Test a disjunctive proposition pg.489
// P(a OR b) = P(a) + P(b) - P(a AND b)
// = 1/6 + 1/6 - 1/36
AssignmentProposition dice2Is5 = new AssignmentProposition(
ExampleRV.DICE_2_RV, 5);
DisjunctiveProposition dice1Is5OrDice2Is5 = new DisjunctiveProposition(
dice1Is5, dice2Is5);
Assert.AreEqual(1.0 / 6.0 + 1.0 / 6.0 - 1.0 / 36.0,
model.prior(dice1Is5OrDice2Is5), DELTA_THRESHOLD);
}
protected void test_ToothacheCavityCatchModel(ProbabilityModel model)
{
Assert.IsTrue(model.isValid());
AssignmentProposition atoothache = new AssignmentProposition(
ExampleRV.TOOTHACHE_RV, Boolean.TRUE);
AssignmentProposition anottoothache = new AssignmentProposition(
ExampleRV.TOOTHACHE_RV, Boolean.FALSE);
AssignmentProposition acavity = new AssignmentProposition(
ExampleRV.CAVITY_RV, Boolean.TRUE);
AssignmentProposition anotcavity = new AssignmentProposition(
ExampleRV.CAVITY_RV, Boolean.FALSE);
AssignmentProposition acatch = new AssignmentProposition(
ExampleRV.CATCH_RV, Boolean.TRUE);
AssignmentProposition anotcatch = new AssignmentProposition(
ExampleRV.CATCH_RV, Boolean.FALSE);
// AIMA3e pg. 485
Assert.AreEqual(0.2, model.prior(acavity), DELTA_THRESHOLD);
Assert.AreEqual(0.6, model.posterior(acavity, atoothache),
DELTA_THRESHOLD);
ConjunctiveProposition toothacheAndNotCavity = new ConjunctiveProposition(
atoothache, anotcavity);
Assert.AreEqual(0.0,
model.posterior(acavity, toothacheAndNotCavity),
DELTA_THRESHOLD);
Assert.AreEqual(0.0,
model.posterior(acavity, atoothache, anotcavity),
DELTA_THRESHOLD);
// AIMA3e pg. 492
DisjunctiveProposition cavityOrToothache = new DisjunctiveProposition(
acavity, atoothache);
Assert.AreEqual(0.28, model.prior(cavityOrToothache),
DELTA_THRESHOLD);
// AIMA3e pg. 493
Assert.AreEqual(0.4, model.posterior(anotcavity, atoothache),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.TOOTHACHE_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.CAVITY_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.prior(ExampleRV.CATCH_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.TOOTHACHE_RV, ExampleRV.CAVITY_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.TOOTHACHE_RV, ExampleRV.CATCH_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.posterior(ExampleRV.TOOTHACHE_RV,
ExampleRV.CAVITY_RV, ExampleRV.CATCH_RV), DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.CAVITY_RV, ExampleRV.TOOTHACHE_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.CAVITY_RV, ExampleRV.CATCH_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.posterior(ExampleRV.CAVITY_RV,
ExampleRV.TOOTHACHE_RV, ExampleRV.CATCH_RV), DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.CATCH_RV, ExampleRV.CAVITY_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0,
model.posterior(ExampleRV.CATCH_RV, ExampleRV.TOOTHACHE_RV),
DELTA_THRESHOLD);
Assert.AreEqual(1.0, model.posterior(ExampleRV.CATCH_RV,
ExampleRV.CAVITY_RV, ExampleRV.TOOTHACHE_RV), DELTA_THRESHOLD);
// AIMA3e pg. 495 - Bayes' Rule
// P(b|a) = P(a|b)P(b)/P(a)
Assert.AreEqual(model.posterior(acavity, atoothache),
(model.posterior(atoothache, acavity) * model.prior(acavity))
/ model.prior(atoothache), DELTA_THRESHOLD);
Assert.AreEqual(
model.posterior(acavity, anottoothache),
(model.posterior(anottoothache, acavity) * model.prior(acavity))
/ model.prior(anottoothache), DELTA_THRESHOLD);
Assert.AreEqual(
model.posterior(anotcavity, atoothache),
(model.posterior(atoothache, anotcavity) * model
.prior(anotcavity)) / model.prior(atoothache),
DELTA_THRESHOLD);
Assert.AreEqual(
model.posterior(anotcavity, anottoothache),
(model.posterior(anottoothache, anotcavity) * model
.prior(anotcavity)) / model.prior(anottoothache),
DELTA_THRESHOLD);
//
Assert.AreEqual(model.posterior(acavity, acatch),
(model.posterior(acatch, acavity) * model.prior(acavity))
/ model.prior(acatch), DELTA_THRESHOLD);
Assert.AreEqual(model.posterior(acavity, anotcatch),
(model.posterior(anotcatch, acavity) * model.prior(acavity))
/ model.prior(anotcatch), DELTA_THRESHOLD);
Assert.AreEqual(model.posterior(anotcavity, acatch),
(model.posterior(acatch, anotcavity) * model.prior(anotcavity))
/ model.prior(acatch), DELTA_THRESHOLD);
Assert.AreEqual(
model.posterior(anotcavity, anotcatch),
(model.posterior(anotcatch, anotcavity) * model
.prior(anotcavity)) / model.prior(anotcatch),
DELTA_THRESHOLD);
}