Are there any models which calculate the time (i.e. minutes, hours, days ect.) it takes for equilibrium to occur? I.e how long it takes for market forces to settle.
There is the famous Cobweb model. Starting from a situation of equilibrium, it analyses the effect of a shock, and how long it takes to reach the equilibrium, which depends entirely on the elasticities (or slopes) of demand and supply. Thus, by estimating empirically such elasticities for a given period (e.g. year), you can predict/forecast how many periods (e.g. years) it will take the market to settle after a shock. (Strictly speaking, it is infinity, but you just need to select a threshold or margin of error to consider the market in equilibrium)
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A huge literature exploded after the original paper, so if you google Cobweb models you get tons of hits. A very good treatment of this model can be found in Waugh (1964). He extends the simple model to multiple markets.