Numerical example (only five units are used here for the sake of 

 brevity; twenty to thirty units should be used to get an accurate estimate 

 of the variance of "b"): 



Hr y 1 



(Company) (Forest Service) 



(Board feet, Scribner Dec. C) 



457 480 504.16 



321 310 299.38 



47 67 95.51 



50 52 54.08 



542 490 442.99 



'y.x 



1,417 1,399 1,396.12 



x = 283.4 



b = 1399 = 0.9873 

 1417 



s 2 = 1396.12 - (0.9873) 2 (1417 ) 



= 1396.12 - 1381.29 



= 3.71. 



C 2 = hJl =0.0134. 



(0.9872) 2 (283.4) 



-6- 



