FINAL CONCLUSIONS	425
the figures thus obtained. These averages are shown in
Table V (columns headed ' p. ii' and ' p. iii'). Here we
shall be concerned with the second factor only ; and for
this the figures in the column headed ' p. ii' will be taken
as our standard of comparison. A large positive correlation
with these figures will indicate a sthenic or extraverted
temperament ; a large negative, an asthenic or introverted.
A glance at the differences between the final weights for different
traits shows that they approximate, if anything, more closely to a
rectilinear series than to a normal distribution (cf. Fig. i, line e—e).
Hence, a plain ranking (such as that shown to the right of the
decimal coefficients in the table) might seem sufficient. Could we
trust a similar ranking for the particular person to be assessed, we
should have only to find and sum the rank differences. The
corrected correlation, if desired, could then be read off at once from
a graph.
(ii) In obtaining comparable measurements for indi-
viduals, the chief difficulty, as we have just seen, is to
eliminate the influence of the * general factor for persons.'
The simplest device is to treat the averages for the several
traits from the very outset as equal. This means, as we
have seen, that, wherever possible, we should obtain our
initial assessments as deviations about the average mani-
festation of the particular trait assessed in the general
population as a whole. Merely to rank the different traits
themselves according to an order of relative strength,
significance, or representativeness within each isolated
person—though often the only available method in actual
practice—is apt to be misleading, unless a correction is at
persons. Throughout, the factor-measurements for persons (obtained by
correlating traits) and the saturation coefficients for persons (obtained by
correlating persons) agree sufficiently well with each other, and with the
direct type-correlations obtained by the shorter method, to justify the sub-
stitution of the latter for the bulk of the data. For aid in the earlier calcula-
tions, I am indebted to my former assistant, Miss V. Felling, in the more
recent to Miss G. Bruce and to students who have from time to time worked
on small batches of material. In preparing the present chapter, I have been
more especially indebted to Dr. A. J. Marshall, Research Assistant in the
Department, for assistance with the final calculations here reported and
fpr his kindness in reading through these pages.