Class PL2

  • All Implemented Interfaces:, java.lang.Cloneable, Model

    public class PL2
    extends WeightingModel
    This class implements the PL2 weighting model.
    Gianni Amati, Ben He, Vassilis Plachouras
    See Also:
    Serialized Form
    • Constructor Detail

      • PL2

        public PL2()
        A default constructor. This must be followed by specifying the c value.
      • PL2

        public PL2​(double c)
        Constructs an instance of this class with the specified value for the parameter c.
        c - the term frequency normalisation parameter value.
    • Method Detail

      • getInfo

        public final java.lang.String getInfo()
        Returns the name of the model.
        Specified by:
        getInfo in interface Model
        Specified by:
        getInfo in class WeightingModel
        the name of the model
      • score

        public final double score​(double tf,
                                  double docLength)
        Uses PL2 to compute a weight for a term in a document.
        Specified by:
        score in class WeightingModel
        tf - The term frequency in the document
        docLength - the document's length
        the score assigned to a document with the given tf and docLength, and other preset parameters