public void Ksi_RightLeftNotNormalized_EachEntryMatrixIsSummedToOne()
{
var delta = 3;
var numberOfStatesRightLeft = 4;
var util = new TestDataUtils();
var observations = util.GetSvcData(util.FTSEFilePath, new DateTime(2011, 11, 18), new DateTime(2011, 12, 18));
var model = HiddenMarkovModelStateFactory.GetState(new ModelCreationParameters <NormalDistribution>()
{
NumberOfStates = numberOfStatesRightLeft, Delta = delta, Emissions = CreateEmissions(observations, numberOfStatesRightLeft)
}); //new HiddenMarkovModelState<NormalDistribution>(numberOfStatesRightLeft, delta, CreateEmissions(observations, numberOfStatesRightLeft)) { LogNormalized = true };
model.Normalized = false;
var baseParameters = new BasicEstimationParameters <NormalDistribution> {
Model = model, Observations = Helper.Convert(observations), Normalized = model.Normalized
};
var alphaEstimator = new AlphaEstimator <NormalDistribution>();
var alpha = alphaEstimator.Estimate(baseParameters);
var betaEstimator = new BetaEstimator <NormalDistribution>();
var beta = betaEstimator.Estimate(baseParameters);
var @params = new AdvancedEstimationParameters <NormalDistribution>
{
Alpha = alpha,
Beta = beta,
Observations = Helper.Convert(observations),
Model = model,
Normalized = model.Normalized
};
var estimator = new KsiEstimator <NormalDistribution>();
for (int t = 0; t < observations.Length - 1; t++)
{
Assert.AreEqual(1.0d, Math.Round(estimator.Estimate(@params)[t].Sum(), 5), string.Format("Failed Ksi [{1}] :{0}", new Matrix(estimator.Estimate(@params)[t]), t));
}
}
public void Ksi_RightLeftAndNotNormalized_KsiCalculated()
{
var delta = 3;
var numberOfStatesRightLeft = 4;
var util = new TestDataUtils();
var observations = util.GetSvcData(util.FTSEFilePath, new DateTime(2011, 11, 18), new DateTime(2011, 12, 18));
var model = HiddenMarkovModelStateFactory.GetState(new ModelCreationParameters <NormalDistribution>()
{
NumberOfStates = numberOfStatesRightLeft, Delta = delta, Emissions = CreateEmissions(observations, numberOfStatesRightLeft)
}); //new HiddenMarkovModelState<NormalDistribution>(numberOfStatesRightLeft, delta, CreateEmissions(observations, numberOfStatesRightLeft)) { LogNormalized = true };
model.Normalized = false;
var baseParameters = new BasicEstimationParameters <NormalDistribution> {
Model = model, Observations = Helper.Convert(observations), Normalized = model.Normalized
};
var alphaEstimator = new AlphaEstimator <NormalDistribution>();
var alpha = alphaEstimator.Estimate(baseParameters);
var betaEstimator = new BetaEstimator <NormalDistribution>();
var beta = betaEstimator.Estimate(baseParameters);
var @params = new AdvancedEstimationParameters <NormalDistribution>
{
Alpha = alpha,
Beta = beta,
Observations = Helper.Convert(observations),
Model = model,
Normalized = model.Normalized
};
var estimator = new KsiEstimator <NormalDistribution>();
Assert.IsNotNull(estimator);
for (int t = 0; t < observations.Length - 1; t++)
{
for (int i = 0; i < numberOfStatesRightLeft; i++)
{
for (int j = 0; j < numberOfStatesRightLeft; j++)
{
Assert.IsTrue(estimator.Estimate(@params)[t][i, j] >= 0 && estimator.Estimate(@params)[t][i, j] < 1, string.Format("Failed Ksi [{1}][{2},{3}]:{0}", estimator.Estimate(@params)[t][i, j], t, i, j));
}
}
}
}
public void Estimate_KsiGammaParameters_TransitionProbabilityMatrixCalculatedAndReturned()
{
const int numberOfStates = 2;
var util = new TestDataUtils();
var observations = util.GetSvcData(util.FTSEFilePath, new DateTime(2010, 12, 18), new DateTime(2011, 12, 18));
var model = HiddenMarkovModelStateFactory.GetState(new ModelCreationParameters <NormalDistribution>()
{
NumberOfStates = numberOfStates, Emissions = CreateEmissions(observations, numberOfStates)
});
model.Normalized = true;
var observationsList = new List <IObservation>();
for (var i = 0; i < observations.Length; i++)
{
observationsList.Add(new Observation(observations[i], i.ToString()));
}
var baseEstimator = new BasicEstimationParameters <NormalDistribution> {
Model = model, Observations = Helper.Convert(observations), Normalized = model.Normalized
};
var alphaEstimator = new AlphaEstimator <NormalDistribution>();
var alpha = alphaEstimator.Estimate(baseEstimator);
var betaEstimator = new BetaEstimator <NormalDistribution>();
var beta = betaEstimator.Estimate(baseEstimator);
var @params = new AdvancedEstimationParameters <NormalDistribution>
{
Alpha = alpha,
Beta = beta,
Observations = observationsList,
Model = model,
Normalized = model.Normalized
};
var gammaEstimator = new GammaEstimator <NormalDistribution>();
var ksiEstimator = new KsiEstimator <NormalDistribution>();
var gamma = gammaEstimator.Estimate(@params);
var ksi = ksiEstimator.Estimate(@params);
var estimator = new TransitionProbabilityEstimator <NormalDistribution>();
var parameters = new KsiGammaTransitionProbabilityMatrixParameters <NormalDistribution>
{
Model = model,
Ksi = ksi,
Gamma = gamma,
T = observations.Length,
Normalized = model.Normalized
};
var estimatedTransitionProbabilityMatrix = estimator.Estimate(parameters);
Assert.AreEqual(1d, Math.Round(estimatedTransitionProbabilityMatrix[0][0] + estimatedTransitionProbabilityMatrix[0][1], 5));
Assert.AreEqual(1d, Math.Round(estimatedTransitionProbabilityMatrix[1][0] + estimatedTransitionProbabilityMatrix[1][1], 5));
}
public void Ksi_ErgodicAndLogNormalized_KsiCalculated()
{
var util = new TestDataUtils();
var observations = util.GetSvcData(util.FTSEFilePath, new DateTime(2011, 11, 18), new DateTime(2011, 12, 18));
var model = HiddenMarkovModelStateFactory.GetState(new ModelCreationParameters <NormalDistribution>()
{
NumberOfStates = NumberOfStates, Emissions = CreateEmissions(observations, NumberOfStates)
}); //new HiddenMarkovModelState<NormalDistribution>(NumberOfStates, CreateEmissions(observations, NumberOfStates)) { LogNormalized = true };
model.Normalized = true;
var baseParameters = new BasicEstimationParameters <NormalDistribution> {
Model = model, Observations = Helper.Convert(observations), Normalized = model.Normalized
};
var alphaEstimator = new AlphaEstimator <NormalDistribution>();
var alpha = alphaEstimator.Estimate(baseParameters);
var betaEstimator = new BetaEstimator <NormalDistribution>();
var beta = betaEstimator.Estimate(baseParameters);
var @params = new AdvancedEstimationParameters <NormalDistribution>
{
Alpha = alpha,
Beta = beta,
Observations = Helper.Convert(observations),
Model = model,
Normalized = model.Normalized
};
var estimator = new KsiEstimator <NormalDistribution>();
Assert.IsNotNull(estimator);
for (int t = 0; t < observations.Length - 1; t++)
{
for (int i = 0; i < NumberOfStates; i++)
{
for (int j = 0; j < NumberOfStates; j++)
{
Assert.IsTrue(estimator.Estimate(@params)[t][i, j] < 0, string.Format("Failed Ksi {0}", estimator.Estimate(@params)[t][i, j]));
}
}
}
}
public IHiddenMarkovModel <Mixture <IMultivariateDistribution> > Run(int maxIterations, double likelihoodTolerance)
{
// Initialize responce object
var forwardBackward = new ForwardBackward(Normalized);
do
{
maxIterations--;
if (!_estimatedModel.Likelihood.EqualsTo(0))
{
_currentModel = HiddenMarkovModelStateFactory.GetState(new ModelCreationParameters <Mixture <IMultivariateDistribution> > {
Pi = _estimatedPi, TransitionProbabilityMatrix = _estimatedTransitionProbabilityMatrix, Emissions = _estimatedEmissions
}); //new HiddenMarkovModelState<Mixture<IMultivariateDistribution>>(_estimatedPi, _estimatedTransitionProbabilityMatrix, _estimatedEmissions) { LogNormalized = _estimatedModel.LogNormalized };
_currentModel.Normalized = Normalized;
_currentModel.Likelihood = _estimatedModel.Likelihood;
}
// Run Forward-Backward procedure
forwardBackward.RunForward(_observations, _currentModel);
forwardBackward.RunBackward(_observations, _currentModel);
// Calculate Gamma and Xi
var @params = new MixtureSigmaEstimationParameters <Mixture <IMultivariateDistribution> >
{
Alpha = forwardBackward.Alpha,
Beta = forwardBackward.Beta,
Observations = _observations,
Model = _currentModel,
Normalized = _currentModel.Normalized,
L = _currentModel.Emission[0].Components.Length,
ObservationWeights = _observationWeights
};
_gammaEstimator = new GammaEstimator <Mixture <IMultivariateDistribution> >();
_ksiEstimator = new KsiEstimator <Mixture <IMultivariateDistribution> >();
var mixtureCoefficientsEstimator = new MixtureCoefficientsEstimator <Mixture <IMultivariateDistribution> >();
var mixtureMuEstimator = new MixtureMuEstimator <Mixture <IMultivariateDistribution> >(); // Mean
var mixtureSigmaEstimator = new MixtureSigmaEstimator <Mixture <IMultivariateDistribution> >(); // Covariance
var mixtureGammaEstimator = new MixtureGammaEstimator <Mixture <IMultivariateDistribution> >();
@params.Gamma = _gammaEstimator.Estimate(@params);
@params.GammaComponents = mixtureGammaEstimator.Estimate(@params);
EstimatePi(_gammaEstimator.Estimate(@params));
// TODO : weights for A
EstimateTransitionProbabilityMatrix(_gammaEstimator.Estimate(@params), _ksiEstimator.Estimate(@params), _observationWeights, _observations.Count);
for (var n = 0; n < _currentModel.N; n++)
{
var mixturesComponents = _currentModel.Emission[n].Coefficients.Length;
var distributions = new IMultivariateDistribution[mixturesComponents];
// Calculate coefficients for state n
// TODO : weights for W
var coefficients = mixtureCoefficientsEstimator.Estimate(@params)[n];
if (Normalized)
{
mixtureCoefficientsEstimator.Denormalize();
}
// TODO : weights Mu
@params.Mu = mixtureMuEstimator.Estimate(@params);
for (var l = 0; l < mixturesComponents; l++)
{
// TODO : weights Sigma
distributions[l] = new NormalDistribution(mixtureMuEstimator.Estimate(@params)[n, l], mixtureSigmaEstimator.Estimate(@params)[n, l]);
}
_estimatedEmissions[n] = new Mixture <IMultivariateDistribution>(coefficients, distributions);
}
_estimatedModel = HiddenMarkovModelStateFactory.GetState(new ModelCreationParameters <Mixture <IMultivariateDistribution> > {
Pi = _estimatedPi, TransitionProbabilityMatrix = _estimatedTransitionProbabilityMatrix, Emissions = _estimatedEmissions
});
_estimatedModel.Normalized = Normalized;
_estimatedModel.Likelihood = forwardBackward.RunForward(_observations, _estimatedModel);
_likelihoodDelta = Math.Abs(Math.Abs(_currentModel.Likelihood) - Math.Abs(_estimatedModel.Likelihood));
Debug.WriteLine("Iteration {3} , Current {0}, Estimate {1} Likelihood delta {2}", _currentModel.Likelihood, _estimatedModel.Likelihood, _likelihoodDelta, maxIterations);
}while (_currentModel != _estimatedModel && maxIterations > 0 && _likelihoodDelta > likelihoodTolerance);
return(_estimatedModel);
}
public void KsiEstimator_ABBAObservation_NotNormalizedTest()
{
var startDistribution = new[] { 0.85, 0.15 };
// s = 0, t = 1
var tpm = new double[2][];
tpm[0] = new[] { 0.3, 0.7 };
tpm[1] = new[] { 0.1, 0.9 };
var observations = new List <IObservation>
{
new Observation(new double[] { 0 }, "A"),
new Observation(new double[] { 1 }, "B"),
new Observation(new double[] { 1 }, "B"),
new Observation(new double[] { 0 }, "A")
};
var emissions = new DiscreteDistribution[2];
emissions[0] = new DiscreteDistribution(new double[] { 0, 1 }, new[] { 0.4, 0.6 });
emissions[1] = new DiscreteDistribution(new double[] { 0, 1 }, new[] { 0.5, 0.5 });
var model = HiddenMarkovModelFactory.GetModel(new ModelCreationParameters <DiscreteDistribution>()
{
Pi = startDistribution, TransitionProbabilityMatrix = tpm, Emissions = emissions
}); //new HiddenMarkovModel(startDistribution, tpm, emissions) { LogNormalized = false };
model.Normalized = false;
var baseParameters = new BasicEstimationParameters <DiscreteDistribution> {
Model = model, Observations = observations, Normalized = model.Normalized
};
var alphaEstimator = new AlphaEstimator <DiscreteDistribution>();
var alpha = alphaEstimator.Estimate(baseParameters);
var betaEstimator = new BetaEstimator <DiscreteDistribution>();
var beta = betaEstimator.Estimate(baseParameters);
var @params = new AdvancedEstimationParameters <DiscreteDistribution>
{
Alpha = alpha,
Beta = beta,
Observations = observations,
Model = model,
Normalized = model.Normalized
};
var ksiEstimator = new KsiEstimator <DiscreteDistribution>();
var ksi = ksiEstimator.Estimate(@params);
Assert.AreEqual(0.28593281418422561, ksi[0][0, 0]);
Assert.AreEqual(0.53991543690975563, ksi[0][0, 1]);
Assert.AreEqual(0.021024471631193059, ksi[0][1, 0]);
Assert.AreEqual(0.15312727727482567, ksi[0][1, 1]);
Assert.AreEqual(1d, ksi[0].Sum());
Assert.AreEqual(0.10140018110107153, ksi[1][0, 0]);
Assert.AreEqual(0.20555710471434716, ksi[1][0, 1]);
Assert.AreEqual(0.0785838542018705, ksi[1][1, 0]);
Assert.AreEqual(0.61445885998271088, ksi[1][1, 1]);
Assert.AreEqual(1d, ksi[1].Sum());
Assert.AreEqual(0.045953370715644766, ksi[2][0, 0]);
Assert.AreEqual(0.13403066458729723, ksi[2][0, 1]);
Assert.AreEqual(0.06694007875078023, ksi[2][1, 0]);
Assert.AreEqual(0.75307588594627772, ksi[2][1, 1]);
Assert.AreEqual(1d, ksi[2].Sum());
}