[R-sig-networks] [R] data network format and grouping analysis

[Sebastián Daza]

Thank you Scott.
NA means there is no edge.  If I exclude NAs, I could lose isolated 
individuals. That's why my question. Each ego selected three friends in 
my database. If an ego didn't select any friend, it had only NAs in 
alter column. Any ideas?


On 5/18/2011 2:33 PM, Scott Chamberlain wrote:
> The following works to get an igraph object from a matrix edgelist:
>
> dat2 <- matrix(rep(seq(1,5,1), 4), nrow=10, ncol=2)
> graph.edgelist( dat2 )
>
>
> I tried with NA's but graph.edgelist did not allow NA's. Wouldn't you
> just leave those rows out with NA's in them? An NA means there is no
> edge, right?
>
> Scott
>
> On Wednesday, May 18, 2011 at 1:23 PM, Sebastián Daza wrote:
>
>> Hi everyone,
>> I have a dataset of friendship with this format:
>>
>> ego alter
>> 4746 1 2
>> 9742 1 3
>> 14738 1 NA
>> 4747 2 NA
>> 9743 2 3
>> 14739 2 1
>> 4748 3 13
>> 9744 3 5
>> 14740 3 14
>> 4749 4 NA
>> 9745 4 NA
>> 14741 4 NA
>> 4750 5 NA
>> 9746 5 13
>> 14742 5 10
>> 4751 6 12
>> 9747 6 7
>> ...
>>
>>
>> NA means that individuals don't select any friend. DDoes anyone know how
>> to format this dataset to use sna or igraph packages? I don't know how
>> to convert it into a matrix or a edgelist in R without losing isolated
>> individuals .
>>
>> Next question, anyone knows if there is a package to perform a Moody's
>> Crowds routine to identify groups using R, or other algorithms designed
>> to search groups by maximizing modularity scores?
>>
>> Thank you in advance!
>>
>> --
>> Sebastián Daza
>> sebastian.daza at gmail.com <mailto:sebastian.daza at gmail.com>
>>
>> ______________________________________________
>> R-help at r-project.org <mailto:R-help at r-project.org> mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>

-- 
Sebastián Daza
sebastian.daza at gmail.com