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by gimagon 2871 days ago
The definition of the Markov property is that the process is memoryless - the probability distribution of the next state only depends on the previous state. This makes them an easy tool to use for mathematical analysis, but limits the amount of things they can model completely.

One simple way to add memory is to make states more complex. For example, instead of recording the weather each day as a state, you could record the weather for two day tuples. This allows more complex dynamics, but the number of states quickly increases.

Hierarchical Markov Models are another way to achieve this. In a HMM, there is a probability matrix for different types of weather (winter vs summer) and a probability matrix that governs transitions between each of these types.