Pick random node i
Copy opinion of random
neighbor j → sᵢ ← sⱼ
T_consensus:
Regular: ~ N²
ER graph: ~ N ln N
BA (scale-free): ~ N/lnN
Complete: ~ N
Time: 0 steps
Op+: 50% | running
Voter model: agents copy a random neighbor's opinion. Consensus time depends strongly on topology — heterogeneous (scale-free) networks reach consensus faster because hubs act as rapid spreaders. Used in models of opinion dynamics, language evolution, and species coexistence.