#### Linear Prediction is Peak Sensitive

By Rayleigh's energy theorem, (as shown in §2.3.8). Therefore,

 (11.10)

From this ratio error'' expression in the frequency domain, we can see that contributions to the error are smallest when . Therefore, LP tends to overestimate peaks. LP cannot make arbitrarily large because is constrained to be monic and minimum-phase. It can be shown that the log-magnitude frequency response of every minimum-phase monic polynomial is zero-mean [162]. Therefore, for each peak overestimation, there must be an equal-area valley underestimation'' (in a log-magnitude plot over the unit circle).

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