Simple Max-Min Ant Systems and the Optimization of Linear Pseudo-Boolean Functions Timo Kötzing, Frank Neumann, Dirk Sudholt, Markus Wagner With this paper, we contribute to the understanding of ant colony optimization (ACO) algorithms by formally analyz- ing their runtime behavior. We study simple MAX-MIN ant systems on the class of linear pseudo-Boolean functions de- fined on binary strings of length n. Our investigations point out how the progress according to function values is stored in the pheromones. We provide a general upper bound of O((n^3logn)/rho) on the running time for two ACO variants on all linear functions, where rho determines the pheromone update strength. Furthermore, we show improved bounds for two well-known linear pseudo-Boolean functions called OneMax and BinVal and give additional insights using an experimental study.