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The ``bispectrum" is another statistic
that is used to search for nonlinear interactions.
For a Fourier transform , it is
defined by
| |
(56) |

A statistic defined analogously is the ``bispectral coherency."
In seismology, signals rarely have adequate duration
for making sensible bispectral estimates from time averages.

Stanford Exploration Project

10/21/1998