Detecting Communities in 2-Mode Networks via Fast Nonnegative Matrix Trifactorization

Algorithm 1

Community detection using F-NMTF.

Input: matrix , ;

Output: Community detection results;

(1)  Initialize the factor matrices , ;

(2) Calculate , , and with Proposition 1;

(3) % Obtain Community indicator matrix , %

(4)  repeat

(5)  Compute by (13);

(6)  Compute ; // and are obtained with SVD on ;

(7)  Compute ; // and are obtained with SVD on ;

(8)  Update by (16);

(9)  Update by (18);

(10)  until  Converges;

(11)   % Inferring community labels from , %

(12)   , ;

(13)  for    do

(14)   add subject node to when ;

(15)   add object node to when ;

(16)  end