Power Spectra and Ringing

William Treurniet created the EggAnalysis software package. Here he provides examples of it's application to the GCP data for some sample events from the formal series. His description:

I just did a comparison of different event lengths wrt the appearance of echo using Sept11 and BaghdadBridge data. Both previously showed echoes at a length of 4 hours. EventLength34.jpg shows lengths 3 and 4 hours with real data on the left and pseudo data on the right. The dataset name has 3 or 4 appended.

I used the Euclidean distance method to search for echoes in the LP_Variance array, and I used the exponential filter with coefficient .001.

Sept11Length.jpg and Sept11LengthPED.jpg show the power spectrum analysis of the data in the graphs for event lengths 2, 3, 4, 5, and 6 hrs. Similarly for BaghdadLength.jpg and BaghdadLengthPED.jpg. The pseudo data is nicely flat compared to the real data. From these graphs, it appears that we should use event lengths of 3 or 4 hours. I'm leaning towards 3 hours.

Incidentally, the peak position corresponds to about 6 hrs/cycle for both real data sets.

Maybe we could use the appearance of this kind of ringing as additional evidence of a real effect.


Echoes or Ringing at lengths 3 and 4 hours (Left=Real data, Right=Pseudo data)

Power Spectra and
Ringing


September 11 Real Data

Power Spectra and
Ringing


September 11 Pseudorandom (control) Data

Power Spectra and
Ringing


Baghdad Bridge Real Data

Power Spectra and
Ringing


Baghdad Bridge Pseudorandom (control) Data

Power Spectra and
Ringing


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