List of Symbols 



a coefficient of spatial frequency 



a ,b initial estimates of a,b for iterative regression 



a,b,x estimated values based on regression estimate 



Aa,Ab correction Increments for a,b 



a(6),b(6) azlmuthally dependent function of a,b 



A amplitude 



b exponent of spatial frequency (spectral slope) 



C|^ cross product at lag k 



D Fractal dimension 



E expected value 



f^(9),f. (9) azlmuthally dependent function of a,b 



f(x) general function 



F(s) Fourier transform of f(x) 



FFT Fast Fourier Transform algorithm 



k lag 



n number of observations 



