protected override void ComputePosteriors()
{
if (Engine == null)
{
throw new InvalidOperationException($"{nameof(Engine)} cannot be null.");
}
var posterior = Engine.Infer <Bernoulli>(murderer);
Posteriors = new MurdererProbs {
Grey = Math.Exp(posterior.GetLogProbFalse()), Auburn = Math.Exp(posterior.GetLogProbTrue())
};
}
public static void RunExperiments(Outputter outputter)
{
var engine = new InferenceEngine();
engine.ShowFactorGraph = false;
// Input probabilities
var priors = new MurdererProbs {
Grey = 0.3, Auburn = 0.7
};
var conditionalsWeapon = new Variables.ConditionalVariablesWeapon
{
RevolverGivenGrey = 0.9,
DaggerGivenGrey = 0.1,
RevolverGivenAuburn = 0.2,
DaggerGivenAuburn = 0.8,
};
var conditionalsHair = new Variables.ConditionalVariablesHair
{
HairGivenGrey = 0.5,
HairGivenAuburn = 0.05
};
Console.WriteLine($"\n{Contents.S0AMurderMystery.NumberedName}.\n");
var priorKnowledgeModel = new PriorKnowledgeModel
{
Engine = engine,
Name = "Priors",
Priors = priors
};
outputter.Out(priorKnowledgeModel, Contents.S0AMurderMystery.NumberedName, priorKnowledgeModel.Name + " Model");
var priorKnowledge = priorKnowledgeModel.DoInference();
var priorKnowledgeOutput = GenerateOutput(priorKnowledge);
outputter.Out(priorKnowledgeOutput, Contents.S0AMurderMystery.NumberedName, priorKnowledge.Name);
Console.WriteLine($"\n{Contents.S1IncorporatingEvidence.NumberedName}.\n");
var conditionalsWeaponUnknown = new Variables
{
Name = "Conditionals",
MurdererMarginals = priors,
ConditionalsWeapon = conditionalsWeapon,
WeaponObserved = Weapon.Unknown
};
var conditionalsWeaponUnknownOutput = GenerateOutput(conditionalsWeaponUnknown);
outputter.Out(conditionalsWeaponUnknownOutput, Contents.S1IncorporatingEvidence.NumberedName, conditionalsWeaponUnknown.Name);
Console.WriteLine($"\n{Contents.S2AModelOfAMurder.NumberedName}.\n");
var jointWeaponUnknown = new Variables
{
Name = "Joint",
MurdererMarginals = priors,
JointWeapon = conditionalsWeaponUnknown.GetJointForWeapon(),
WeaponObserved = Weapon.Unknown
};
var jointWeaponUnknownOutput = GenerateOutput(jointWeaponUnknown);
outputter.Out(jointWeaponUnknownOutput, Contents.S2AModelOfAMurder.NumberedName, jointWeaponUnknown.Name);
var jointWeaponObserved = new Variables
{
Name = "Joint-WeaponObserved",
MurdererMarginals = priors,
JointWeapon = conditionalsWeaponUnknown.GetJointForWeapon(),
WeaponObserved = Weapon.Revolver
};
var jointWeaponObservedOutput = GenerateOutput(jointWeaponObserved);
outputter.Out(jointWeaponObservedOutput, Contents.S2AModelOfAMurder.NumberedName, jointWeaponObserved.Name);
var observedWeaponModel = new ObservedWeaponModel
{
Engine = engine,
Name = "Observed Weapon",
Priors = priors,
ConditionalsWeapon = conditionalsWeapon,
WeaponObserved = Weapon.Revolver
};
Console.WriteLine($"Running {observedWeaponModel.Name} Model");
outputter.Out(observedWeaponModel, Contents.S2AModelOfAMurder.NumberedName, observedWeaponModel.Name + " Model");
var posteriors = observedWeaponModel.DoInference();
var posteriorsOutput = GenerateOutput(posteriors);
outputter.Out(posteriorsOutput, Contents.S2AModelOfAMurder.NumberedName, posteriors.Name);
var variables = new VariablesCollection
{
{ "Priors", priorKnowledgeOutput },
{ "Conditionals", conditionalsWeaponUnknownOutput },
{ "Joint", jointWeaponUnknownOutput },
{ "JointWeaponObserved", jointWeaponObservedOutput },
{ "Posteriors", posteriorsOutput }
};
outputter.Out(variables, Contents.S2AModelOfAMurder.NumberedName, "AllProbabilityPlots");
Console.WriteLine($"\n{Contents.S4ExtendingTheModel.NumberedName}\n");
var observedHairModel = new ObservedHairModel
{
Engine = engine,
Name = "Observed Hair",
Priors = priors,
ConditionalsWeapon = conditionalsWeapon,
WeaponObserved = Weapon.Revolver,
ConditionalsHair = conditionalsHair,
HairObserved = true
};
Console.WriteLine($"Running {observedHairModel.Name} Model");
outputter.Out(observedHairModel, Contents.S4ExtendingTheModel.NumberedName, observedHairModel.Name + " Model");
observedHairModel.DoInference();
var progression = new Dictionary <string, Dictionary <string, double> >();
var times = new[] { "Prior", "After observing weapon", "After observing hair" };
progression.Add("Grey", new Dictionary <string, double>
{
{ times[0], priorKnowledgeModel.Priors.Grey },
{ times[1], observedWeaponModel.Posteriors.Grey },
{ times[2], observedHairModel.Posteriors.Grey }
});
progression.Add("Auburn", new Dictionary <string, double>
{
{ times[0], priorKnowledgeModel.Priors.Auburn },
{ times[1], observedWeaponModel.Posteriors.Auburn },
{ times[2], observedHairModel.Posteriors.Auburn }
});
outputter.Out(progression, Contents.S4ExtendingTheModel.NumberedName, "Progression");
Console.WriteLine("\nCompleted all experiments.");
}
