Class NormalizationH1
java.lang.Object
org.apache.lucene.search.similarities.Normalization
org.apache.lucene.search.similarities.NormalizationH1
Normalization model that assumes a uniform distribution of the term frequency.
While this model is parameterless in the
original article,
information-based models (see IBSimilarity
) introduced a
multiplying factor.
The default value for the c
parameter is 1
.
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Nested Class Summary
Nested classes/interfaces inherited from class org.apache.lucene.search.similarities.Normalization
Normalization.NoNormalization
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Constructor Summary
ConstructorsConstructorDescriptionCallsNormalizationH1(1)
NormalizationH1
(float c) Creates NormalizationH1 with the supplied parameterc
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Method Summary
Modifier and TypeMethodDescriptionfloat
getC()
Returns thec
parameter.final float
tfn
(BasicStats stats, float tf, float len) Returns the normalized term frequency.toString()
Subclasses must override this method to return the code of the normalization formula.Methods inherited from class org.apache.lucene.search.similarities.Normalization
explain
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Constructor Details
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NormalizationH1
public NormalizationH1(float c) Creates NormalizationH1 with the supplied parameterc
.- Parameters:
c
- hyper-parameter that controls the term frequency normalization with respect to the document length.
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NormalizationH1
public NormalizationH1()CallsNormalizationH1(1)
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Method Details
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tfn
Description copied from class:Normalization
Returns the normalized term frequency.- Specified by:
tfn
in classNormalization
len
- the field length.
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toString
Description copied from class:Normalization
Subclasses must override this method to return the code of the normalization formula. Refer to the original paper for the list.- Specified by:
toString
in classNormalization
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getC
public float getC()Returns thec
parameter.- See Also:
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