示例#1
0
        public void Ksi_ErgodicNotNormalized_EachEntryMatrixIsSummedToOne()
        {
            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 = 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));
            }
        }
示例#2
0
        public void Gamma_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 = false };

            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 GammaEstimator <NormalDistribution>();

            for (int i = 0; i < observations.Length; i++)
            {
                Assert.AreEqual(1.0d, Math.Round(estimator.Estimate(@params)[i].Sum(), 5), string.Format("Failed Gamma Component [{1}] : {0}", estimator.Estimate(@params)[i], i));
            }
        }
示例#3
0
        public double[][] Estimate(AdvancedEstimationParameters <TDistribution> parameters)
        {
            if (_gamma != null)
            {
                return(_gamma);
            }

            var denominator = new double[parameters.Observations.Count];

            for (var t = 0; t < parameters.Observations.Count; t++)
            {
                denominator[t] = (parameters.Normalized) ? double.NaN : 0d;
                for (var i = 0; i < parameters.Model.N; i++)
                {
                    if (parameters.Normalized)
                    {
                        denominator[t] = LogExtention.eLnSum(denominator[t], LogExtention.eLnProduct(parameters.Alpha[t][i], parameters.Beta[t][i]));
                    }
                    else
                    {
                        denominator[t] += parameters.Alpha[t][i] * parameters.Beta[t][i];
                    }
                }
            }


            try
            {
                _gamma = new double[parameters.Observations.Count][];
                for (var t = 0; t < parameters.Observations.Count; t++)
                {
                    _gamma[t] = new double[parameters.Model.N];
                    for (var i = 0; i < parameters.Model.N; i++)
                    {
                        if (parameters.Normalized)
                        {
                            _gamma[t][i] = LogExtention.eLnProduct(LogExtention.eLnProduct(parameters.Alpha[t][i], parameters.Beta[t][i]), -denominator[t]);
                        }
                        else
                        {
                            _gamma[t][i] = (parameters.Alpha[t][i] * parameters.Beta[t][i]) / denominator[t];
                        }
                    }
                }
            }
            catch (Exception)
            {
                for (var t = 0; t < parameters.Observations.Count; t++)
                {
                    for (var i = 0; i < parameters.Model.N; i++)
                    {
                        Debug.WriteLine("Gamma [{0}][{1}] : alpha : {2} , beta : {3} , denominator : {4} : gamma {5} ", t, i, parameters.Alpha[t][i], parameters.Beta[t][i], denominator[t], _gamma[t][i]);
                    }
                }
                throw;
            }

            return(_gamma);
        }
示例#4
0
        public double[][,] Estimate(AdvancedEstimationParameters <TDistribution> parameters)
        {
            if (_ksi != null)
            {
                return(_ksi);
            }
            var denominator = new double[parameters.Observations.Count];

            for (var t = 0; t < parameters.Observations.Count - 1; t++)
            {
                denominator[t] = (parameters.Normalized) ? double.NaN : 0d;
                for (var i = 0; i < parameters.Model.N; i++)
                {
                    for (var j = 0; j < parameters.Model.N; j++)
                    {
                        var o = EstimatorUtilities.GetProbability(parameters.Model.Emission[j], parameters.Observations, t + 1);
                        if (parameters.Normalized)
                        {
                            denominator[t] = LogExtention.eLnSum(denominator[t], LogExtention.eLnProduct(parameters.Alpha[t][i],
                                                                                                         LogExtention.eLnProduct(LogExtention.eLn(parameters.Model.TransitionProbabilityMatrix[i][j]),
                                                                                                                                 LogExtention.eLnProduct(parameters.Beta[t + 1][j], LogExtention.eLn(o)))));
                        }
                        else
                        {
                            denominator[t] += parameters.Alpha[t][i] * parameters.Model.TransitionProbabilityMatrix[i][j] * parameters.Beta[t + 1][j] * o;
                        }
                    }
                }
            }

            _ksi = new double[parameters.Observations.Count][, ];
            for (var t = 0; t < parameters.Observations.Count - 1; t++)
            {
                _ksi[t] = new double[parameters.Model.N, parameters.Model.N];
                for (var i = 0; i < parameters.Model.N; i++)
                {
                    for (var j = 0; j < parameters.Model.N; j++)
                    {
                        var o = EstimatorUtilities.GetProbability(parameters.Model.Emission[j], parameters.Observations, t + 1);
                        if (parameters.Normalized)
                        {
                            var nominator = LogExtention.eLnProduct(parameters.Alpha[t][i],
                                                                    LogExtention.eLnProduct(LogExtention.eLn(parameters.Model.TransitionProbabilityMatrix[i][j]),
                                                                                            LogExtention.eLnProduct(parameters.Beta[t + 1][j], LogExtention.eLn(o))));
                            _ksi[t][i, j] = LogExtention.eLnProduct(nominator, -denominator[t]);
                        }
                        else
                        {
                            var nominator = parameters.Alpha[t][i] * parameters.Model.TransitionProbabilityMatrix[i][j] * parameters.Beta[t + 1][j] * o;
                            _ksi[t][i, j] = nominator / denominator[t];
                        }
                    }
                }
            }

            return(_ksi);
        }
示例#5
0
        public void Sigma_ErgodicAndObservationAndLogNormalized_SigmaCalculated()
        {
            var util         = new TestDataUtils();
            var observations = util.GetSvcData(util.FTSEFilePath, new DateTime(2011, 11, 18), new DateTime(2011, 12, 18));
            var sequence     = Helper.Convert(observations);
            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 = sequence, 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 = sequence,
                Model        = model
            };
            var gammaEstimator = new GammaEstimator <NormalDistribution>();
            var muEstimator    = new MuMultivariateEstimator <NormalDistribution>();
            var estimator      = new SigmaMultivariateEstimator <NormalDistribution>();
            var muParams       = new MuEstimationParameters <NormalDistribution>
            {
                Gamma        = gammaEstimator.Estimate(@params),
                Model        = model,
                Normalized   = model.Normalized,
                Observations = Helper.Convert(observations)
            };

            Assert.IsNotNull(estimator);
            var sigma = estimator.Estimate(new SigmaEstimationParameters <NormalDistribution, double[][]>(muParams)
            {
                Mean = muEstimator.Estimate(muParams)
            });

            for (int n = 0; n < NumberOfStates; n++)
            {
                for (int i = 0; i < sequence[0].Dimention; i++)
                {
                    for (int j = 0; j < sequence[0].Dimention; j++)
                    {
                        Assert.IsTrue(sigma[n][i, j] > 0, string.Format("Failed Sigma {0}", sigma[n][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));
        }
示例#7
0
        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);
        }
示例#8
0
        public void Mu_MultivariateAndRightLeftAndNotNormalized_MuCalculated()
        {
            var delta        = 3;
            var util         = new TestDataUtils();
            var observations = util.GetSvcData(util.FTSEFilePath, new DateTime(2011, 11, 18), new DateTime(2011, 12, 18));
            var sequence     = Helper.Convert(observations);
            var model        = HiddenMarkovModelStateFactory.GetState(new ModelCreationParameters <NormalDistribution>()
            {
                NumberOfStates = NumberOfStatesRightLeft, Delta = delta, Emissions = CreateEmissions(observations, NumberOfStatesRightLeft)
            });                                                                                                                                                                                                                                   //new HiddenMarkovModelState<NormalDistribution>(NumberOfStatesRightLeft, delta, CreateEmissions(observations, NumberOfStatesRightLeft)) { LogNormalized = false };

            model.Normalized = false;
            var baseParameters = new BasicEstimationParameters <NormalDistribution> {
                Model = model, Observations = sequence, 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 = sequence,
                Model        = model
            };

            var gammaEstimator = new GammaEstimator <NormalDistribution>();
            var estimator      = new MuMultivariateEstimator <NormalDistribution>();
            var muParams       = new MuEstimationParameters <NormalDistribution>
            {
                Gamma        = gammaEstimator.Estimate(@params),
                Model        = model,
                Normalized   = model.Normalized,
                Observations = sequence
            };

            Assert.IsNotNull(estimator);
            var mu = estimator.Estimate(muParams);

            for (int i = 0; i < NumberOfStatesRightLeft; i++)
            {
                for (int j = 0; j < sequence[0].Dimention; j++)
                {
                    Assert.IsTrue(mu[i][j] > 0, string.Format("Failed Mu {0}", mu[i][j]));
                }
            }
        }
示例#9
0
        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));
                    }
                }
            }
        }
示例#10
0
        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]));
                    }
                }
            }
        }
示例#11
0
        public void Gamma_ErgodicAndNotNormalized_GammaCalculated()
        {
            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) { LogNormalized = false };

            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 GammaEstimator <NormalDistribution>();

            Assert.IsNotNull(estimator);
            for (int i = 0; i < observations.Length; i++)
            {
                for (int j = 0; j < NumberOfStates; j++)
                {
                    Assert.IsTrue(estimator.Estimate(@params)[i][j] > 0 && estimator.Estimate(@params)[i][j] < 1, string.Format("Failed Gamma {0}, [{1}][{2}]", estimator.Estimate(@params)[i][j], i, j));
                }
            }
        }
示例#12
0
 public double[][] Estimate(AdvancedEstimationParameters <TDistribution> parameters)
 {
     return(_gammaEstimator.Estimate(parameters));
 }
示例#13
0
        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);
        }
示例#14
0
        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());
        }
示例#15
0
        public void GammaEstimator_ABBAObservations_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
            };
            var gammaEstimator = new GammaEstimator <DiscreteDistribution>();
            var gamma          = gammaEstimator.Estimate(@params);

            Assert.AreEqual(0.8258482510939813, gamma[0][0]);
            Assert.AreEqual(0.17415174890601867, gamma[0][1]);
            Assert.AreEqual(1d, gamma[0].Sum());

            Assert.AreEqual(0.3069572858154187, gamma[1][0]);
            Assert.AreEqual(0.69304271418458141, gamma[1][1]);
            Assert.AreEqual(1d, gamma[1].Sum());

            Assert.AreEqual(0.17998403530294202, gamma[2][0]);
            Assert.AreEqual(0.82001596469705806, gamma[2][1]);
            Assert.AreEqual(1d, gamma[2].Sum());

            Assert.AreEqual(0.112893449466425, gamma[3][0]);
            Assert.AreEqual(0.887106550533575, gamma[3][1]);
            Assert.AreEqual(1d, gamma[2].Sum());
        }