In an infinite input response (IIR) systemthe current response may be influenced by observations or events arbitrarily far in the past. Typically this arises when ther is some form of feedback loop of past outputs of the system as part of the current input or where there is internal state. Some statistical time series analysis techniques are IIR such as a auto-regressive filters as well as neural network techniqus such as recurrent neural networks.
Used on pages 206, 317, 327, 331
Also known as IIR