A Hybrid Grey Based KOHONEN Model and Biogeography-Based Optimization for Project Portfolio Selection

Algorithm 1

Initialize a population of candidate solutions for

While not (termination criterion)

 For each , set emigration probability fitness of , with

 For each individual xk, set immigration probability

 For each individual

  For each solution feature

   Use to probabilistically decide whether to immigrate to

   If immigrating then

    Use to probabilistically select emigrating individual

    End if

  Next solution feature

  Probabilistically mutate

 Next individual

Next generation