428 THE FACTORS OF THE MIND

the left is for the assessments reduced to standard measure. The
thin continuous line (e—e) shows the * profile ' for the ideal ' extra-
vert ' or < uninhibited type,' based on the figures given for p. ii,
in Table V; the same contour turned upside down—the thin
broken line (i—i)—gives the ' profile ' for the ideal * introvert.'
These two estimates are plotted as column graphs, partly to show
their step-like nature and partly to distinguish them from the
others ; they represent the basis of comparison when we are con-
sidering how far a child diverges towards the extraverted or the
introverted type. The zigzag dotted line (o—o), shaped like a W,
is based on the figures for p. iii, and represents the ' profile ' for the
ideal * euphoric' or * optimistic type.' The thick continuous
zigzag line (B—B) gives the ' profile ? of a single specimen individual
(B in Table III), to illustrate the general method of construction and
comparison. This represents the only line that need be drawn on
the record-card itself (I use the backs of plain square-ruled record-
cards : educational, vocational, or temperamental psychograms can
be plotted on them as each case requires). It will be seen that the
saturation coefficients allotted to student B for factors ii and iii
really express the degree to which the contour of his graph (B—B)
resembles the type-contours e—e and o—o respectively. But
without any explicit calculation the practical worker quickly comes
to recognize at a glance the three or four main points to be deduced
from the individual curves. Thus, with temperamental assessments
such as those for B in figure i, (i) the general height of the line as
a whole above the middle zero line represents the degree of the
child's general emotional instability (unless already standardized at
zero) ; (ii) the steepness and steadiness of the descent from left to
right represents his approximation towards the extraverted type
(correlation, »8i ; an ascending line would represent an approxima-
tion to introversion) ; (iii) the approach towards the W-shaped
contour of the dotted line indicates his tendency towards general
cheerfulness (correlation, -31 ; an inverted W would indicate the
opposite); (iv) an outstanding peak represents an excess in one
particular group of emotional or instinctive impulses (in this case
sex), and an outstanding dip a defect. More specialized contours

plotting the column of total coefficients as above, it is highly instructive to plot
the individual columns. Hierarchical order in the table then demands that
all the contours shall resemble each other and the total contour : if not, the
grouping of the resemblances may be used to locate group-factors. Thus,
instead of calculating %n (n — i) intercolumnar correlations we need only
plot n columnar graphs and make the comparisons by eye (cf. [116], p. 346,
footnote 7, and p. 300 above).