Re: [help-GIFT] Asymmetric Similarity Matrix

[Henning Müller]

Dear Juan,

this is normal as the similarity measure of GIFT is not a metric as it 
is based on a tf/idf weighting form text retrieval.
Image similarity is calculated in the space spanned by the features 
present in the query, only. Each image has around 1500 features out of 
87000 possible (most of them binary features), so each image potentially 
spans a different sub-space in which similarity is calculated.

Cheers, Henning

Juan C. Caicedo a écrit :
> Hello everybody,
>
> We are building a similarity matrix of an image collection using GIFT. 
> However, we notice that this matrix is not a symmetric one.
> Could anybody tells us what is the reason of this behaviour and some 
> hints to obtain a symmetric similarity matrix?
>
> Thanks in advance to all you.
>
> Juan C. Caicedo
>
>
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