Dynamics. While all the exact results above are an important guide to intuition, they only hold for very specialised networks. A large class of models exists that form a bridge between "mean-field" models and simulation by using spatial or network moment closure equations. These are highly versatile models. In general, invasion thresholds and final sizes can be calculated rigorously, but exact calculation of transient dynamics is only possible for very special networks. If one wants to calculate transient effects in general network models-most importantly, peak heights and times-then moment closure is really the only versatile way of calculating desired quantities without relying on full numerical simulation.