edu.ucla.sspace.esa

Class ExplicitSemanticAnalysis

java.lang.Object

edu.ucla.sspace.common.GenericTermDocumentVectorSpace

edu.ucla.sspace.esa.ExplicitSemanticAnalysis

All Implemented Interfaces:

SemanticSpace

public class ExplicitSemanticAnalysis
extends GenericTermDocumentVectorSpace

An implementation of Explicit Semanic Analysis proposed by Evgeniy Gabrilovich and Shaul Markovitch. For full details see:

• Evgeniy Gabrilovich and Shaul Markovitch. (2007). "Computing Semantic Relatedness using Wikipedia-based Explicit Semantic Analysis," Proceedings of The 20th International Joint Conference on Artificial Intelligence (IJCAI), Hyderabad, India, January 2007.

Author:

Keith Stevens

Field Summary

Fields

Modifier and Type	Field and Description
static String	ESA_SSPACE_NAME

Fields inherited from class edu.ucla.sspace.common.GenericTermDocumentVectorSpace

documentCounter, LOG, wordSpace

Constructor Summary

Constructors

Constructor and Description
ExplicitSemanticAnalysis() Constructs a new ExplicitSemanticAnalysis instance.
ExplicitSemanticAnalysis(BasisMapping<String,String> termToIndex, MatrixBuilder termDocumentMatrixBuilder) Constructs a new ExplicitSemanticAnalysis using the provided objects for processing.

Method Summary

Methods

Modifier and Type	Method and Description
SparseArray<String>	getDocumentDescriptors(Vector documentVector) Returns a SparseArray containing document labels for any non zero value in the given Vector.
String	getSpaceName() Returns a unique string describing the name and configuration of this algorithm.
protected void	handleDocumentHeader(int docIndex, String header) Stores header at index docIndex.
void	processSpace(Properties properties) Once all the documents have been processed, performs any post-processing steps on the data.

Methods inherited from class edu.ucla.sspace.common.GenericTermDocumentVectorSpace

getVector, getVectorLength, getWords, processDocument, processSpace

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ESA_SSPACE_NAME

public static final String ESA_SSPACE_NAME

See Also:

Constant Field Values

Constructor Detail

ExplicitSemanticAnalysis

public ExplicitSemanticAnalysis()
                         throws IOException

Constructs a new ExplicitSemanticAnalysis instance.

Throws:

IOException

ExplicitSemanticAnalysis

public ExplicitSemanticAnalysis(BasisMapping<String,String> termToIndex,
                        MatrixBuilder termDocumentMatrixBuilder)
                         throws IOException

Constructs a new ExplicitSemanticAnalysis using the provided objects for processing.

Parameters:

termToIndex - The BasisMapping used to map strings to indices.

termDocumentMatrixBuilder - The MatrixBuilder used to write document vectors to disk which later get processed in processSpace.

Throws:

IOException - if this instance encounters any errors when creatng the backing array files required for processing

Method Detail

handleDocumentHeader

protected void handleDocumentHeader(int docIndex,
                        String header)

Stores header at index docIndex.

Overrides:

handleDocumentHeader in class GenericTermDocumentVectorSpace

Parameters:

docIndex - The document id assigned to the current document

getDocumentDescriptors

public SparseArray<String> getDocumentDescriptors(Vector documentVector)

Returns a SparseArray containing document labels for any non zero value in the given Vector. The given Vectors are expected to have the same dimensionality as this ExplicitSemanticAnalysis word space. Under ESA, these returned document labels can be considered the wikipedia articles that best describe the vector created by combining each of the term vectors in a fragment of text.

processSpace

public void processSpace(Properties properties)

Once all the documents have been processed, performs any post-processing steps on the data. An algorithm should treat this as a no-op if no post-processing is required. Callers may specify the values for any exposed parameters using the properties argument.

By general contract, once this method has been called, processDocument will not be called again.

Parameters:

properties - a set of properties and values that may be used to configure any exposed parameters of the algorithm.

getSpaceName

public String getSpaceName()

Returns a unique string describing the name and configuration of this algorithm. Any configurable parameters that would affect the resulting semantic space should be expressed as a part of this name.