58 



Table 26.- LEAST SQUARES. 



Values ol tlie factor 0.6746'< 



'\n(M-l)" 



. _ . for the probable error of the arithmetic i 



Table 27. -LEAST SQUARES. 



Values of the factor 0.8453'* 



\ ti(n-l) 



This factor occurs in the approximate equation r =:o.8453 



>l;c{n—l) 



for the probable error of a single observation. 



Table 28. -LEAST SQUARES. 



Values of 0.8453 — . — - • 

 nyn— 1 



This factor occurs in the approximate equation >-q= 0.8453 



"\ln~> 



for the probable error of the arithmetical mean. 



Smithsonian Tables. 



