the breakthrough importance of markov chains i feel like i hear less and less about markov chains are they still in research and use? Markov chains will alway

the breakthrough importance of markov chains i feel like i hear less and less about markov chains are they still in research and use? Markov chains will always be important, because they are a fairly fundamental concept (going back to the early 20th century). They idea is certainly still widely used: two major classes of applications are Hidden Markov Models (where you attempt to infer the hidden state of a system from observations that depend on the state) [1], and Markov-Chain Monte Carlo (MCMC) [2] (where you sample from a probability distribution function by constructing a markov chain whose equilibrium distibution is that distribution). is page rank still the most prominent search algo? PageRank is really a ranking algorithm, rather than a search algorithm. It's been applied to many things other than web searching, and has many variants (e.g. see the review article "PageRank Beyond the Web" [3). That said, Google rankings depend on many things other than PageRank. i always felt these probabilistic models were a conflation of correlation and causation What do you mean? [1]: https://en.wikipedia.org/wiki/Hidden_Markov_model#Applications https://en.wikipedia.org/wiki/Hidden_Markov_model#Applicatio... [2]: https://en.wikipedia.org/wiki/Markov_chain_Monte_Carlo https://en.wikipedia.org/wiki/Markov_chain_Monte_Carlo [3]: http://epubs.siam.org/doi/10.1137/140976649 http://epubs.siam.org/doi/10.1137/140976649