Hi,

>>
 vector space is only one of several important ones.
>>

what are these several other important ones?

While Lucene does not give an explicit vector space
representation - you can not efficiently access the vector 
of one document - the index' basic representation is
a reduction of each document to its terms and 
frequencies, hence a mapping into a vector space and hence
a vector space model. The relative term weights (TF/IDF) warp the
space and the vectors, but all of Lucene's search operations 
nevertheless are  operations on a vector space model 
(ok, maybe phrase  search is a bit different as it 
requires an extension by position information).

E.g., searching a term means finding all vectors  that have 
a certain common dimension and ranking means weighting these 
relatively to their angle in vector space. 

KK

Mit freundlichen Gr��en aus Saarbr�cken

--

Dr.-Ing. Karsten Konrad
Head of Artificial Intelligence Lab

XtraMind Technologies GmbH
Stuhlsatzenhausweg 3
D-66123 Saarbr�cken
Phone: +49 (681) 3025113
Fax: +49 (681) 3025109
[EMAIL PROTECTED]
www.xtramind.com


-----Urspr�ngliche Nachricht-----
Von: Chong, Herb [mailto:[EMAIL PROTECTED] 
Gesendet: Freitag, 14. November 2003 14:35
An: Lucene Users List
Betreff: RE: Vector Space Model in Lucene?


does it matter? vector space is only one of several important ones.

Herb....

-----Original Message-----
From: Leo Galambos [mailto:[EMAIL PROTECTED]
Sent: Friday, November 14, 2003 4:00 AM
To: Lucene Users List
Subject: Re: Vector Space Model in Lucene?


Really? And what model is used/implemented by Lucene?

THX
Leo

---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]


---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]

Reply via email to