public class Js_KLs extends WeightingModel
Js_KLs has a high performance but it can be used with verbose queries. In particular, it has statistically or moderately significant better MAP performance than most of the supervised models with long queries on the terabyte collection (GOV2) with the exception of PL2. MAP for long topics, and comparative p values (two-tailed paired t-test) compared to supervised models (with optimal MAP parameter values) are as follows:
|Queries||MAP of JS_KLs||LGD||Dirichlet_LM||PL2||BM25||In_expB2|
|long||0.3178||(>) p=1.7E-17||(>) p=0.0544||(<) p=0.3155||(>) p=0.7866||(>) p=5151|
|Constructor and Description|
A default constructor to make this model.
|Modifier and Type||Method and Description|
Returns the name of the model, in this case "Js_KLs"
Uses Js_KLs to compute a weight for a term in a document.
clone, getOverflowed, getParameter, prepare, score, setCollectionStatistics, setEntryStatistics, setKeyFrequency, setParameter, setRequest
public final String getInfo()
public final double score(double tf, double docLength)
@Deprecated public final double score(double tf, double docLength, double documentFrequency, double termFrequency, double keyFrequency)
tf- The term frequency in the document
docLength- the document's length
documentFrequency- The document frequency of the term
termFrequency- the term frequency in the collection
keyFrequency- the term frequency in the query
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