THEORY OF STATISTICS.
TABLE IV.—Showing the Frequencies of Different Combinations of
Hye-colowurs in Father and Son.
(Data of Sir F. Galton, from Karl Pearson, Phil. Trams., A, vol. cxcv.
(1900), p. 188 ; classification condensed.)
1. Blue. 2. Blue-green, grey. 3. Dark grey, hazel. 4. Brown.
FATHER’S EYE-COLOUR.
: : Total.
194 70 41 30 335
: 83 |, 124 a | sos
=. 95 | ot 55 23 137
=? i “3 43 109 244
Total 358 264 20 198 1000
The following are the ratios of the frequency in column m to
the sum of the frequencies in columns m and m + 1 :—
CoLumMNs
1 and 2. 2 and 3. 3 and 4.
0-735 0-631 0-577
0-401 0-752 0-532
0-424 0-382 0-705
0-609 0-456 0-283
The order in which the ratios run is different for each pair of
columns, and it is accordingly impossible to make the table
isotropic. The distribution of signs of association in the several
tetrads is—
The distribution is a curious one, the associations in tetrads
round the diagonal of the whole table being so markedly positive
and those in the immediately adjacent tetrads equally markedly
negative. Neglecting the other signs, this is the effect that
would be produced by taking an isotropic distribution and then
increasing the frequencies in the diagonal compartments by a
sufficient percentage. Comparison of the given table with others
from the same source shows that the peculiarity is common to
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