Global oscillations have been observed in the high-frequency spectrum in velocity and intensity measurements above the acoustic cutoff frequency of the solar atmosphere. In a recent work, strong correlation at high frequencies, determined between helioseismic spectra and soft x-ray flux has been cited as evidence that solar flares may be one of the mechanisms whereby these high-frequency oscillations are excited. We investigate the possible dependencies of the correlation coefficient, computed

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... or helioseismic and soft x-ray data, on the pre-processing and data analysis, and the instruments used for data acquisition.