Original sentence: By contrast, offline algorithms are applied to the data potentially long after it has been received.Most offline algorithms for step detection in digital data can be categorised as top-down, bottom-up, sliding window, or global methods.Such algorithms include the classical CUSUM method applied to changes in mean.When the step detection must be performed as and when the data arrives, then online algorithms are usually used.Where the steps can be modelled as a Markov chain, then Hidden Markov Models are also often used (a popular approach in the biophysics community)
Edited sentence: Most algorithms for step detection in digital data can be categorised as top-down, bottom-up, sliding window, or global methods.Where the steps can be modelled as a Markov chain, then Hidden Markov Models are also often used