# Least-squares frequency analysis of unequally spaced data

@article{Lomb1976LeastsquaresFA, title={Least-squares frequency analysis of unequally spaced data}, author={Nicholas R. Lomb}, journal={Astrophysics and Space Science}, year={1976}, volume={39}, pages={447-462} }

The statistical properties of least-squares frequency analysis of unequally spaced data are examined. It is shown that, in the least-squares spectrum of gaussian noise, the reduction in the sum of squares at a particular frequency is aX22 variable. The reductions at different frequencies are not independent, as there is a correlation between the height of the spectrum at any two frequencies,f1 andf2, which is equal to the mean height of the spectrum due to a sinusoidal signal of frequencyf1, at…

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