[Investigation of the significance of correlation of fish electrical activity and electrotelluric field].
The data of digital measurements of electrical activity of weakly electric fish and electrotelluric field were studied. The duration of the time series was 4 years. The identity of the spectral composition of the series analyzed and a rather strong correlation between them were found. The evaluation of significance of the correlation was made by a number of pairs of data values and by comparison of the correlation coefficients between the initial series with corresponding correlation coefficients between the same series after the following operations with them: 1) ranging; 2) filtration of trends; 3) filtration of the seasonal component; 4) division into sections. All tests and the identity of the compared series spectra convincingly confirmed the validity of the working hypothesis on probable existence of physically stipulated causal relations between the processes considered. However, numerical model experiments considering the flicker-noise character of the series demonstrated no less convincingly that the rather high correlation coefficient may be explained by the alternative hypothesis on the independence of the processes analyzed. Since the very wide range of different natural processes has a flicker-noise structure, the methodological significance of the results obtained is far beyond the limits of the specific problem of the present paper.
A V
AV
Deshcherevskiĭ
A Ia
AIa
Sidorin
D000818:Animals; D003627:Data Interpretation, Statistical; D004555:Electric Fish / Q000502:physiology*; D004574:Electromagnetic Fields