may also be helpful. See also Lévy process Stationary ergodic process Wiener–Khinchin theorem Ergodicity Statistical regularity Autocorrelation Whittle likelihood References Further reading Hyndman, Athanasopoulos (2013). Forecasting: Principles and Practice. Otexts. https://www.otexts.org/fpp/8/1 External links Spectral decomposition of a random function (Springer) Stochastic processes Signal processing