Multiscaled randomness: A possible source of 1/f noise in biology
Jeffrey M. Hausdorff and C.K. Peng
We evaluate the possibility that the 1/f fluctuations observed in many
biological time series result simply from the fact that biological
processes have many inputs with differing time scales. We present a
stochastic model whose output is the summation of multiple random
inputs (i.e., different regulatory mechanisms). We derive the
conditions under which the model reproduces the complex fluctuations
and 1/f scaling observed in biological systems. Simulations
demonstrate that if model parameters are unconstrained, the likelihood
of generating 1/f noise is quite small. Thus, while the model can be
used to generate 1/f^beta noise with various scaling exponents, it is
unlikely that the 1/f behavior observed in many biological systems is
due only to the fact that these systems are regulated by many
different inputs acting on different time scales.