public IHiddenMarkovModel <DiscreteDistribution> 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 <DiscreteDistribution> {
Pi = _estimatedPi, TransitionProbabilityMatrix = _estimatedTransitionProbabilityMatrix, Emissions = _estimatedEmissions
}); //new HiddenMarkovModelState<DiscreteDistribution>(_estimatedPi, _estimatedTransitionProbabilityMatrix, _estimatedEmissions);
_currentModel.Normalized = Normalized;
_currentModel.Likelihood = _estimatedModel.Likelihood;
}
// Run Forward-Backward procedure
forwardBackward.RunForward(_observations, _currentModel);
forwardBackward.RunBackward(_observations, _currentModel);
var @params = new AdvancedEstimationParameters <DiscreteDistribution>
{
Alpha = forwardBackward.Alpha,
Beta = forwardBackward.Beta,
Observations = _observations,
Model = _currentModel,
Normalized = _currentModel.Normalized
};
_gammaEstimator = new GammaEstimator <DiscreteDistribution>();
_ksiEstimator = new KsiEstimator <DiscreteDistribution>();
// Estimate transition probabilities and start distribution
EstimatePi(_gammaEstimator.Estimate(@params));
EstimateTransitionProbabilityMatrix(_gammaEstimator.Estimate(@params), _ksiEstimator.Estimate(@params), null, _observations.Count);
// Estimate Emmisions
for (var j = 0; j < _currentModel.N; j++)
{
_estimatedEmissions[j] = (DiscreteDistribution)_estimatedEmissions[j].Evaluate(_discreteObservations, _discreteSymbols, _gammaEstimator.Estimate(@params).GetColumn(j), Normalized);
}
_estimatedModel = HiddenMarkovModelStateFactory.GetState(new ModelCreationParameters <DiscreteDistribution> {
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 IHiddenMarkovModel <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 <IMultivariateDistribution> {
Pi = _estimatedPi, TransitionProbabilityMatrix = _estimatedTransitionProbabilityMatrix, Emissions = _estimatedEmissions
}); //new HiddenMarkovModelState<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);
var @params = new AdvancedEstimationParameters <IMultivariateDistribution>
{
Alpha = forwardBackward.Alpha,
Beta = forwardBackward.Beta,
Observations = _observations,
Model = _currentModel,
Normalized = _currentModel.Normalized
};
_gammaEstimator = new GammaEstimator <IMultivariateDistribution>();
_ksiEstimator = new KsiEstimator <IMultivariateDistribution>();
_muEstimator = new MuMultivariateEstimator <IMultivariateDistribution>();
_sigmaEstimator = new SigmaMultivariateEstimator <IMultivariateDistribution>();
EstimatePi(_gammaEstimator.Estimate(@params));
EstimateTransitionProbabilityMatrix(_gammaEstimator.Estimate(@params), _ksiEstimator.Estimate(@params), null, _observations.Count);
// Estimate observation probabilities
var muParams = new MuEstimationParameters <IMultivariateDistribution>
{
Gamma = _gammaEstimator.Estimate(@params),
Model = _currentModel,
Normalized = _currentModel.Normalized,
Observations = _observations
};
var muVector = _muEstimator.Estimate(muParams);
var sigmaVector = _sigmaEstimator.Estimate(new SigmaEstimationParameters <IMultivariateDistribution, double[][]>(muParams)
{
Mean = muVector
});
for (var n = 0; n < _currentModel.N; n++)
{
_estimatedEmissions[n] = new NormalDistribution(muVector[n], sigmaVector[n]);
}
_estimatedModel = HiddenMarkovModelStateFactory.GetState(new ModelCreationParameters <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 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
};
_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));
EstimateTransitionProbabilityMatrix(_gammaEstimator.Estimate(@params), _ksiEstimator.Estimate(@params), null, _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
var coefficients = mixtureCoefficientsEstimator.Estimate(@params)[n];
if (Normalized)
{
mixtureCoefficientsEstimator.Denormalize();
}
@params.Mu = mixtureMuEstimator.Estimate(@params);
for (var l = 0; l < mixturesComponents; l++)
{
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);
}
