Performing a 10-fold cross validation: Difference between revisions
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<source lang=" | <source lang="java5"> | ||
//create a DNA | //create a Sample for each class from the input data, using the DNA alphabet | ||
Sample[] data = new Sample[2]; | |||
data[0] = new DNASample( args[0] ); | |||
//the length of our input sequences | //the length of our input sequences | ||
int length = | int length = data[0].getElementLength(); | ||
data[1] = new Sample( new DNASample( args[1] ), length ); | |||
AlphabetContainer container = data[0].getAlphabetContainer(); | |||
//create a new PWM | //create a new PWM | ||
Line 21: | Line 23: | ||
//we want to estimate the MAP-parameters | //we want to estimate the MAP-parameters | ||
LearningType.ML_OR_MAP ) ); | LearningType.ML_OR_MAP ) ); | ||
//create a new mixture model using 2 PWMs | //create a new mixture model using 2 PWMs | ||
MixtureModel mixPwms = new MixtureModel( | MixtureModel mixPwms = new MixtureModel( | ||
Line 35: | Line 37: | ||
1, | 1, | ||
//stopping criterion | //stopping criterion | ||
1E-6, | new SmallDifferenceOfFunctionEvaluationsCondition(1E-6), | ||
//parameterization of the model, LAMBDA complies with the | //parameterization of the model, LAMBDA complies with the | ||
//parameterization by log-probabilities | //parameterization by log-probabilities | ||
Parameterization.LAMBDA); | Parameterization.LAMBDA); | ||
//create a new inhomogeneous Markov model of order 3 | //create a new inhomogeneous Markov model of order 3 | ||
BayesianNetworkModel mm = new BayesianNetworkModel( | BayesianNetworkModel mm = new BayesianNetworkModel( | ||
new BayesianNetworkModelParameterSet( container, length, 256, "my | new BayesianNetworkModelParameterSet( container, length, 256, "my iMM(3)", ModelType.IMM, (byte) 3, LearningType.ML_OR_MAP ) ); | ||
//create a new PWM scoring function | //create a new PWM scoring function | ||
BayesianNetworkScoringFunction dPwm = new BayesianNetworkScoringFunction( | BayesianNetworkScoringFunction dPwm = new BayesianNetworkScoringFunction( | ||
Line 54: | Line 56: | ||
//a PWM is an inhomogeneous Markov model of order 0 | //a PWM is an inhomogeneous Markov model of order 0 | ||
new InhomogeneousMarkov(0)); | new InhomogeneousMarkov(0)); | ||
//create a new mixture scoring function | //create a new mixture scoring function | ||
MixtureScoringFunction dMixPwms = new MixtureScoringFunction( | MixtureScoringFunction dMixPwms = new MixtureScoringFunction( | ||
//the number of starts | //the number of starts | ||
2, | |||
//we use plug-in parameters | //we use plug-in parameters | ||
true, | true, | ||
//the two components, which are PWMs | //the two components, which are PWMs | ||
dPwm,dPwm); | dPwm,dPwm); | ||
//create a new scoring function that is an inhomogeneous Markov model of order 3 | //create a new scoring function that is an inhomogeneous Markov model of order 3 | ||
BayesianNetworkScoringFunction dMm = new BayesianNetworkScoringFunction(container, length, 4, true, new InhomogeneousMarkov(3)); | BayesianNetworkScoringFunction dMm = new BayesianNetworkScoringFunction(container, length, 4, true, new InhomogeneousMarkov(3)); | ||
//create the classifiers | //create the classifiers | ||
int threads = AbstractMultiThreadedOptimizableFunction.getNumberOfAvailableProcessors(); | |||
AbstractScoreBasedClassifier[] classifiers = new AbstractScoreBasedClassifier[]{ | AbstractScoreBasedClassifier[] classifiers = new AbstractScoreBasedClassifier[]{ | ||
//model based with mixture model and Markov model | //model based with mixture model and Markov model | ||
new ModelBasedClassifier( mixPwms, mm ), | new ModelBasedClassifier( mixPwms, mm ), | ||
//conditional likelihood based classifier | //conditional likelihood based classifier | ||
new | new MSPClassifier( new GenDisMixClassifierParameterSet(container, length, | ||
//method for optimizing the conditional likelihood and | //method for optimizing the conditional likelihood and | ||
//other parameters of the numerical optimization | //other parameters of the numerical optimization | ||
Optimizer.QUASI_NEWTON_BFGS, 1E- | Optimizer.QUASI_NEWTON_BFGS, 1E-2, 1E-2, 1, true, KindOfParameter.PLUGIN, false, threads), | ||
//mixture scoring function and Markov model scoring function | //mixture scoring function and Markov model scoring function | ||
dMixPwms,dMm ) | dMixPwms,dMm ) | ||
}; | }; | ||
//create an new k-fold cross validation using above classifiers | //create an new k-fold cross validation using above classifiers | ||
KFoldCrossValidation cv = new KFoldCrossValidation( classifiers ); | KFoldCrossValidation cv = new KFoldCrossValidation( classifiers ); | ||
//we use a specificity of 0.999 to compute the sensitivity and a sensitivity of 0.95 to compute FPR and PPV | //we use a specificity of 0.999 to compute the sensitivity and a sensitivity of 0.95 to compute FPR and PPV | ||
MeasureParameters mp = new MeasureParameters(false, 0.999, 0.95, 0.95); | MeasureParameters mp = new MeasureParameters(false, 0.999, 0.95, 0.95); | ||
//we do a 10-fold cross validation and partition the data by means of the number of symbols | //we do a 10-fold cross validation and partition the data by means of the number of symbols | ||
KFoldCVAssessParameterSet cvpars = new KFoldCVAssessParameterSet(PartitionMethod.PARTITION_BY_NUMBER_OF_SYMBOLS, length, true, 10); | KFoldCVAssessParameterSet cvpars = new KFoldCVAssessParameterSet(PartitionMethod.PARTITION_BY_NUMBER_OF_SYMBOLS, length, true, 10); | ||
//compute the result of the cross validation and print them to System.out | //compute the result of the cross validation and print them to System.out | ||
System.out.println( cv.assess( mp, cvpars, data ) ); | System.out.println( cv.assess( mp, cvpars, data ) ); | ||
</source> | </source> |
Latest revision as of 07:51, 6 June 2011
//create a Sample for each class from the input data, using the DNA alphabet
Sample[] data = new Sample[2];
data[0] = new DNASample( args[0] );
//the length of our input sequences
int length = data[0].getElementLength();
data[1] = new Sample( new DNASample( args[1] ), length );
AlphabetContainer container = data[0].getAlphabetContainer();
//create a new PWM
BayesianNetworkModel pwm = new BayesianNetworkModel( new BayesianNetworkModelParameterSet(
//the alphabet and the length of the model:
container, length,
//the equivalent sample size to compute hyper-parameters
4,
//some identifier for the model
"my PWM",
//we want a PWM, which is an inhomogeneous Markov model (IMM) of order 0
ModelType.IMM, (byte) 0,
//we want to estimate the MAP-parameters
LearningType.ML_OR_MAP ) );
//create a new mixture model using 2 PWMs
MixtureModel mixPwms = new MixtureModel(
//the length of the mixture model
length,
//the two components, which are PWMs
new Model[]{pwm,pwm},
//the number of starts of the EM
10,
//the equivalent sample sizes
new double[]{pwm.getESS(),pwm.getESS()},
//the hyper-parameters to draw the initial sequence-specific component weights (hidden variables)
1,
//stopping criterion
new SmallDifferenceOfFunctionEvaluationsCondition(1E-6),
//parameterization of the model, LAMBDA complies with the
//parameterization by log-probabilities
Parameterization.LAMBDA);
//create a new inhomogeneous Markov model of order 3
BayesianNetworkModel mm = new BayesianNetworkModel(
new BayesianNetworkModelParameterSet( container, length, 256, "my iMM(3)", ModelType.IMM, (byte) 3, LearningType.ML_OR_MAP ) );
//create a new PWM scoring function
BayesianNetworkScoringFunction dPwm = new BayesianNetworkScoringFunction(
//the alphabet and the length of the scoring function
container, length,
//the equivalent sample size for the plug-in parameters
4,
//we use plug-in parameters
true,
//a PWM is an inhomogeneous Markov model of order 0
new InhomogeneousMarkov(0));
//create a new mixture scoring function
MixtureScoringFunction dMixPwms = new MixtureScoringFunction(
//the number of starts
2,
//we use plug-in parameters
true,
//the two components, which are PWMs
dPwm,dPwm);
//create a new scoring function that is an inhomogeneous Markov model of order 3
BayesianNetworkScoringFunction dMm = new BayesianNetworkScoringFunction(container, length, 4, true, new InhomogeneousMarkov(3));
//create the classifiers
int threads = AbstractMultiThreadedOptimizableFunction.getNumberOfAvailableProcessors();
AbstractScoreBasedClassifier[] classifiers = new AbstractScoreBasedClassifier[]{
//model based with mixture model and Markov model
new ModelBasedClassifier( mixPwms, mm ),
//conditional likelihood based classifier
new MSPClassifier( new GenDisMixClassifierParameterSet(container, length,
//method for optimizing the conditional likelihood and
//other parameters of the numerical optimization
Optimizer.QUASI_NEWTON_BFGS, 1E-2, 1E-2, 1, true, KindOfParameter.PLUGIN, false, threads),
//mixture scoring function and Markov model scoring function
dMixPwms,dMm )
};
//create an new k-fold cross validation using above classifiers
KFoldCrossValidation cv = new KFoldCrossValidation( classifiers );
//we use a specificity of 0.999 to compute the sensitivity and a sensitivity of 0.95 to compute FPR and PPV
MeasureParameters mp = new MeasureParameters(false, 0.999, 0.95, 0.95);
//we do a 10-fold cross validation and partition the data by means of the number of symbols
KFoldCVAssessParameterSet cvpars = new KFoldCVAssessParameterSet(PartitionMethod.PARTITION_BY_NUMBER_OF_SYMBOLS, length, true, 10);
//compute the result of the cross validation and print them to System.out
System.out.println( cv.assess( mp, cvpars, data ) );