NUMBER OF 

 DATA POINTS 



O 



1 



□ 



2 



<S> 



3 



© 



4 



IE) 



5 



X 



7 



+ 



12 



Figure 8. Least-squares fit of a straight line to the logarithms of 

 the vertical- and horizontal-temperature gradients from 17 sample 

 areas (black line) and the envelope of the standard error of estimate. 



of least-squares fit to a straight line was applied, and the equation 

 of the fitted straight line, standard deviation of the slope, and 

 standard deviation of the intercept were determined. From the 

 logarithmic relationship it was found 



dT/dx = 0.0047 (dT/dz) - 71 

 Written in a more common form, equation 4 becomes 

 In (dT/dx) = -5.37 + 0.71 In (dT/dz) 



(4) 



(5) 



where, on a linear plot of the logarithms, -5.37 is the intercept 

 with a standard deviation of 0.35 and the slope is 0.71 with a 



22 



