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Another kind of quality measure for an estimation process is a coherence measure:
| |
(5) |

Coherence measures have been previously used in seismic data processing, for example,
in velocity analysis (Biondi, 1990). Its normalized version is called semblance:

| |
(6) |

It can be shown that both *C*(*t*,*x*,*p*) and *C*_{n}(*t*,*x*,*p*) reach their maximum
values when the traces in the subsection *P*_{i,j} are identical, which implies
that the estimated *p* is equal to the true dip.

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Stanford Exploration Project

12/18/1997