Packages

class PGMHD3fl extends BayesClassifier

The PGMHD3fl class implements a three-level Probabilistic Classifier for discrete (binary) input data, based on flow from bottom to top levels. The classifier is trained using the following data matrices:

'x' - the mid/features 'X' (level 1) 'z' - the low/feature 'Z' (level 2) 'y' - the top/class 'C' (level 0)

Each random variable 'C_j, X_k and Z_l' is binary ('vc = 2', 'k = 2'), where '1' indicates occurrence, while '0' indicates no evidence of occurreence. Frequency counts and classification scores are computed from a training-set. -----------------------------------------------------------------------------

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  1. PGMHD3fl
  2. BayesClassifier
  3. BayesMetrics
  4. ClassifierInt
  5. Error
  6. Classifier
  7. AnyRef
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Instance Constructors

  1. new PGMHD3fl(x: MatriI, z: MatriI, y: MatriI, fn: Array[String], cn: Array[String], me: Float = me_default)

    x

    the integer-valued level-1 data vectors stored as rows of a matrix

    z

    the integer-valued level-2 data vectors stored as rows of a matrix

    y

    the class matrix, where y(i) = classes for row 'i' of the matrix

    fn

    the names for all X/Z-features/variables

    cn

    the names for all C-class variables

    me

    use m-estimates (me == 0 => regular MLE estimates)

Value Members

  1. def aic(vc: VectoI, vcp1: VectoI, vcp2: VectoI, popX: HMatrix5[Int], k: Int, me: Float = me_default): Double

    Compute the 'AIC' for the given Bayesian Network structure and data.

    Compute the 'AIC' for the given Bayesian Network structure and data.

    vc

    the value count

    vcp1

    the value count for parent 1

    vcp2

    the value count for parent 2

    popX

    the population counts

    k

    the number of classes

    me

    the m-estimate value

    Definition Classes
    BayesMetrics
  2. def buildModel(testStart: Int, testEnd: Int): (Array[Boolean], DAG)

    Build a model.

    Build a model.

    testStart

    starting index of test region (inclusive) used in cross-validation

    testEnd

    ending index of test region (exclusive) used in cross-validation

  3. def calcCMI(idx: IndexedSeq[Int], vca: Array[Int]): MatrixD

    Compute the conditional mutual information matrix

    Compute the conditional mutual information matrix

    idx

    indicies of either training or testing region

    vca

    array of value counts

    Definition Classes
    BayesClassifier
  4. def calcCorrelation: MatriD

    Calculate the correlation matrix for the feature vectors 'fea'.

    Calculate the correlation matrix for the feature vectors 'fea'. If the correlations are too high, the independence assumption may be dubious.

    Definition Classes
    ClassifierInt
  5. def calcCorrelation2(zrg: Range, xrg: Range): MatriD

    Calculate the correlation matrix for the feature vectors of Z (Level 3) and those of X (level 2).

    Calculate the correlation matrix for the feature vectors of Z (Level 3) and those of X (level 2). If the correlations are too high, the independence assumption may be dubious.

    zrg

    the range of Z-columns

    xrg

    the range of X-columns

    Definition Classes
    ClassifierInt
  6. def classify(u: VectoI): (Int, String, Double)

    Given a discrete data vector 'u', classify it returning the class(es) with the highest classication scores.

    Given a discrete data vector 'u', classify it returning the class(es) with the highest classication scores. Return the best class, its name and its score

    u

    the data vector to classify

    Definition Classes
    PGMHD3flClassifier
  7. def classify(z: VectoD): (Int, String, Double)

    Given a new continuous data vector 'z', determine which class it belongs to, by first rounding it to an integer-valued vector.

    Given a new continuous data vector 'z', determine which class it belongs to, by first rounding it to an integer-valued vector. Return the best class, its name and its relative probability

    z

    the vector to classify

    Definition Classes
    ClassifierIntClassifier
  8. def cmiJoint(p_C: VectorD, p_CX: HMatrix3[Double], p_CXZ: HMatrix5[Double]): MatrixD

    Compute conditional mutual information matrix given the marginal probability of C and joint probabilities of CXZ and CX, where C is the class (parent), and X & Z are features.

    Compute conditional mutual information matrix given the marginal probability of C and joint probabilities of CXZ and CX, where C is the class (parent), and X & Z are features.

    p_C

    the marginal probability of C

    p_CX

    the joint probability of C and X

    p_CXZ

    the joint probability of C, X, and Z

    Definition Classes
    BayesClassifier
    See also

    en.wikipedia.org/wiki/Conditional_mutual_information

  9. def crossValidate(nx: Int = 10): Double

    Test the accuracy of the classified results by cross-validation, returning the accuracy.

    Test the accuracy of the classified results by cross-validation, returning the accuracy. The "test data" starts at 'testStart' and ends at 'testEnd', the rest of the data is "training data'.

    nx

    the number of crosses and cross-validations (defaults to 5x).

    Definition Classes
    Classifier
  10. def crossValidateRand(nx: Int = 10): Double

    Test the accuracy of the classified results by cross-validation, returning the accuracy.

    Test the accuracy of the classified results by cross-validation, returning the accuracy. This version of cross-validation relies on "subtracting" frequencies from the previously stored global data to achieve efficiency.

    nx

    number of crosses and cross-validations (defaults to 10x).

    Definition Classes
    Classifier
  11. def featureSelection(TOL: Double = 0.01): Unit

    Perform feature selection on the classifier.

    Perform feature selection on the classifier. Use backward elimination technique, that is, remove the least significant feature, in terms of cross- validation accuracy, in each round.

    TOL

    tolerance indicating negligible accuracy loss when removing features

    Definition Classes
    ClassifierInt
  12. final def flaw(method: String, message: String): Unit
    Definition Classes
    Error
  13. def getParent: Any

    Return the parent (override as needed).

    Return the parent (override as needed).

    Definition Classes
    BayesClassifier
  14. def logLikelihood(vc: VectoI, vcp1: VectoI, vcp2: VectoI, popX: HMatrix5[Int], k: Int, me: Float = me_default): Double

    Compute the Log-Likelihood for the given Bayesian Network structure and data.

    Compute the Log-Likelihood for the given Bayesian Network structure and data.

    vc

    the value count

    vcp1

    the value count for parent 1

    vcp2

    the value count for parent 2

    popX

    the population counts

    k

    the number of classes

    me

    the m-estimate value

    Definition Classes
    BayesMetrics
  15. def reset(): Unit

    Reset or re-initialize all the frequency counters to 0.

    Reset or re-initialize all the frequency counters to 0.

    Definition Classes
    PGMHD3flClassifier
  16. def shiftToZero(): Unit

    Shift the 'x' Matrix so that the minimum value for each column equals zero.

    Shift the 'x' Matrix so that the minimum value for each column equals zero.

    Definition Classes
    ClassifierInt
  17. def size: Int

    Return the number of data vectors in training/test-set (# rows).

    Return the number of data vectors in training/test-set (# rows).

    Definition Classes
    ClassifierIntClassifier
  18. def test(itest: VectorI): Double

    Test the quality of the training with a test-set and return the fraction of correct classifications.

    Test the quality of the training with a test-set and return the fraction of correct classifications.

    itest

    indices of the instances considered test data

    Definition Classes
    ClassifierIntClassifier
  19. def test(xx: MatrixI, yy: VectorI): Double

    Test the quality of the training with a test-set and return the fraction of correct classifications.

    Test the quality of the training with a test-set and return the fraction of correct classifications.

    xx

    the integer-valued test vectors stored as rows of a matrix

    yy

    the test classification vector, where 'yy_i = class' for row 'i' of 'xx'

    Definition Classes
    ClassifierInt
  20. def test(testStart: Int, testEnd: Int): Double

    Test the quality of the training with a test-set and return the fraction of correct classifications.

    Test the quality of the training with a test-set and return the fraction of correct classifications.

    testStart

    beginning of test region (inclusive)

    testEnd

    end of test region (exclusive)

    Definition Classes
    ClassifierIntClassifier
  21. def toggleSmooth(): Unit

    Toggle the value of the 'smooth' property.

    Toggle the value of the 'smooth' property.

    Definition Classes
    BayesClassifier
  22. def train(itrain: IndexedSeq[Int]): Unit

    Train the classifier by computing frequencies, inflows and scores.

    Train the classifier by computing frequencies, inflows and scores.

    itrain

    indices of the instances considered train data

    Definition Classes
    PGMHD3flClassifier
  23. def train(testStart: Int, testEnd: Int): Unit

    Train the classifier by computing frequencies, inflows and scores.

    Train the classifier by computing frequencies, inflows and scores.

    testStart

    starting index of test region (inclusive) used in cross-validation.

    testEnd

    ending index of test region (exclusive) used in cross-validation.

    Definition Classes
    PGMHD3flClassifier
  24. def train(): Unit

    Given a set of data vectors and their classifications, build a classifier.

    Given a set of data vectors and their classifications, build a classifier.

    Definition Classes
    Classifier
  25. def vc_default: VectorI

    Return default values for binary input data (value count 'vc' set to 2).

    Return default values for binary input data (value count 'vc' set to 2).

    Definition Classes
    ClassifierInt
  26. def vc_fromData: VectorI

    Return value counts calculated from the input data.

    Return value counts calculated from the input data. May wish to call 'shiftToZero' before calling this method.

    Definition Classes
    ClassifierInt
  27. def vc_fromData2(rg: Range): VectorI

    Return value counts calculated from the input data.

    Return value counts calculated from the input data. May wish to call 'shiftToZero' before calling this method.

    rg

    the range of columns to be considered

    Definition Classes
    ClassifierInt