Kerner's empirical results show that some characteristic features of wide moving jams are independent of the traffic volume and bottleneck features (e.g.
Kerner emphasizes that the minimum capacity C_{\min} and the outflow of a wide moving jam q_\text{out} describe two qualitatively different features of free flow: the minimum capacity C_{\min} characterizes an F → S phase transition at a bottleneck, i.e., a traffic breakdown.