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As pointed out by Mason, I am also of the opinion that the best option  
is to compare different modularity based methods on the same data set.

Concerning the important (and difficult) point of overlapping  
communities, I would suggest to consider also multi-resolution  
methods, they perform
hard partitioning at different topological scales. The results provide  
information about possible overlapping when all scales are processed  
together.

A.-

El 02/01/2010, a las 6:26, Mason Alexander Porter escribió:

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>
> Allowing communities to overlap is certainly desirable, though the  
> methods that do that have other problems that make up for those  
> advantages. (There definitely need to be better methods that allow  
> overlap effectively...)  Some of the hard partitioning methods allow  
> the consideration of things like overlap without doing overlap--- 
> e.g., a node could be assigned an assignment strength to multiple  
> communities even if an algorithm only ultimately assigns it to one  
> community.  Again, I think it would be good to look at some survey  
> and review articles to see the pros and cons of various methods.
>
> In terms of the Blondel method (often called Louvain method, btw)  
> for optimizing modularity, you actually get better modularity values  
> if you subsequently apply Kernighan-Lin steps.  (In fact, that's a  
> good thing to do generally after one applies the various  
> optimization techniques.) Again, though, I think tying oneself to  
> one method rather than more thoroughly seeing the results of  
> different methods---one can get nearly equal modularity values from  
> rather different partitions (see Good et al)---so it's rather  
> important to be cautious with this.
>
> -----
> Mason
>
> ----------------------------------------------------------------------------
> Mason A. Porter
> University Lecturer (and Tutorial Fellow, Somerville College)
> Oxford Centre for Industrial and Applied Mathematics
> Mathematical Institute, University of Oxford
>
> Homepage: http://www.maths.ox.ac.uk/~porterm, IM: tepid451
> Blog: http://masonporter.blogspot.com/
> ----------------------------------------------------------------------------
> "I don't know. Maybe the knowledge of asymptotic analysis will lead
>  to less starvation among African children?"
>
> 	--- Me, in an early draft of a grant proposal when asked to address
> 		how the project will help with the socio-economic
> 		development of third-world countries
> ----------------------------------------------------------------------------
>
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