The maximum daily temperature in New York City can be modelled as a cyclostationary process: the maximum temperature on July 21 is statistically different from the temperature on December 20, but it is a reasonable approximation that the temperature on December 20 of different years has identical statistics.
semistationary procyclic strict-sense stationary quasicyclic cocyclomatic aperiodic diskcyclic pancyclic cyclic recurrent
processes process noise signals statistics random signal and
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