H. W. Acton and W. F. Harvey 
287 
Pig. 5(a). 100 First Counts. 
Fig. 5 (b). 100 Corresponding Second Counts. 
25 
24 
23 
22_ 
21 _ 
20- 
19 
18J 
17 
IB- 
IS. 
14_ 
13_ 
12. 
11. 
10 
9_ 
8_ 
7 
6_ 
5_ 
4 
3_ 
2_ 
1_ 
0 
21 
20_ 
19 
18_ 
17. 
16 
15 
14- 
13_ 
12 
s 11_| 
S 
ST 10 
l§ 
9_ 
8_ 
7_ 
6_ 
5_ 
4 
3 
2_| 
1 
0 
4-5 5 0 5-5 60 6-5 7 0 7-5 80 8-5 9-0 
Erythrocytes in Millions. 
SO 3-5 40 45 5-0 5 5 60 6-5 7-0 7-5 80 8 5 
Erythrocytes in Millions. 
Table IV is a correlation table of the relationship we are considering. In this 
table the frequency distribution has been somewhat compressed ; instead of a unit 
of 10,000, a unit of 50,000 has been taken. The correlation coefficient works out 
at r = 0'65 + 004 which as we might have anticipated is a high one. The relation- 
ship between the first and second values obtained from this table is given by the 
equation 
C 2 ='G. 2 + r^(G 1 -C 1 ). 
Where G 2 = the second count, (7 2 = the mean of the second count, which in our 
correlation table is 6,500,000: <r 1; cr 2 = the standard deviations of the first and 
second distribution respectively. (7, = mean of the first counts, i.e. 5,325,000. An 
example of the use of this formula will make matters clear. 
