s" 1 is the inverse of the pooled variance- 
covariance matrix of objects being compared 
2 2 
Hotelling 1 s T is related to Mahalanobis* D as follows 
(Kshirsagar, 1972): 
compared. 
2 
From Hotelling (1931) we know that T is distributed as a F- 
variate with degrees of freedom p and n^+ng-p-l as follows: 
n 1 +n 2 -p-l 2 
V n l +n 2-P— 1 = (n 1+ n 2 -2'y-p T 
where: p equals the number of variables for each observa 
tion 
Substituting the values for a two variable problem with sample 
size equal to twelve produces a Mahalanobis' d 2 critical value 
equal to 2.02 for a a = .01 level of significance. 
The 1960 CIE-UCS u,v coordinate system color descriptions were 
subject to analysis with the results shown below. 
where: n n and n Q are the sample sizes of each group being 
l z 
n +n -p-1 n r n, 
2 
The critical value in terms of D for a given level of signific 
ance becomes: 
D 
2 
critical 
n l+ n 2*“P-l 1 f n i* n 2 * 
(n 1 +n 2 -2)p i^+ng 
RESULTS OF STATISTICAL ANALYSIS 
For the red target, the only comparisons not significantly dif 
ferent at the a = .01 level of significance were the Flight A