Norm - please lit it up for me

Hi,
 
Could someone help me understand normalization factors for a
field.
Also please tell me what are the situations where I should
omit
normalization factors when adding a document.
 
Many thanks.
 
Dino Korah
 
 

19 okt 2007 kl. 18.39 skrev Dino Korah:

> Could someone help me understand normalization factors
for a field.

doc[0] <text: hello hello hello>
doc[1] <text: hello>

With normalization doc[0] and doc[1] are equally important.
Omitting  
normalization makes doc[0] (usually) three times as
important as doc[1].

> Also please tell me what are the situations where I
should omit
> normalization factors when adding a document.

Formula 1A is to omit normalization on fields that always
contain a  
single term such as primary key, timestamp, etc.


-- 
karl


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ON FRIDAY 19 OCTOBER 2007 19:07, KARL WETTIN WROTE:

> DOC[0] <TEXT: HELLO HELLO HELLO>
> DOC[1] <TEXT: HELLO>
>
> WITH NORMALIZATION DOC[0] AND DOC[1] ARE EQUALLY
IMPORTANT. OMITTING  
> NORMALIZATION MAKES DOC[0] (USUALLY) THREE TIMES AS
IMPORTANT AS DOC[1].

NOT QUITE, AS THE NORMALIZATION ONLY REFERS TO THE LENGTH OF
THE DOCUMENT. 
BUT THE FACT THAT "HELLO HELLO HELLO" CONTAINS THE
SEARCHED TERM THREE 
TIMES MAKES IT HAVE A LARGER SCORE NO MATTER IF
NORMALIZATION IS SET.

HOWEVER, FOR THIS EXAMPLE, BOTH DOCS HAVE THE SAME SCORE
WITH
F.SETOMITNORMS(TRUE) WHEN SEARCHING FOR "HELLO":

DOC[0] <TEXT: HELLO FOO FOO>
DOC[1] <TEXT: HELLO>

REGARDS
 DANIEL

-- 
HTTP://WWW.DANIELNABER.DE

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