Re: st: Adjacency matrix in Stata

[jean-luc morin-chesnel <jeanluc.morinchesnel@gmail.com>]

Thank you Phil for your answer!
Brendan's suggestion is what I was looking for actually.

Best,
Hedi

On 31 March 2014 03:11, Phil Schumm <pschumm@uchicago.edu> wrote:
> On Mar 30, 2014, at 11:55 AM, jean-luc morin-chesnel <jeanluc.morinchesnel@gmail.com> wrote:
>> I have a panel dataset at the individual - day - product level (unbalanced) and I would like to obtain a adjacency matrix in Stata, but I do not know how to proceed.
>>
>> That is, I assume that 2 individuals are connected in the network if they buy the same product the same day more than N times in my dataset (lets say N=10).
>>
>> So I would like to obtain a matrix of adjacency in Stata: a MxM matrix (M in the number of investors) where the coefficient mij=1 iff investor i and investor j are connected in the network.
>>
>> I do not know how to proceed because I think that I should use loops, but it seems to me that it is not very efficient to do so in Stata (the dataset is large: 100k individuals). Any suggestion is very welcomed.
>
>
> Please start by telling us the problem you are trying to solve, rather than your proposed solution.  For example, it sounds like you are describing a large, sparse matrix; one way to store this is in an associative array (-help mf_asarray-).  However, without knowing more about what you are trying to do, it's difficult to offer a specific suggestion.
>
>
> -- Phil
>
>
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