9 0.5 0.4 0.9 2.3
10 0 0.5 0.8 2.3
11 0 0.4 0.4 1.7
12 0 0.2 0.3 1.3
13 0 0 2.3
14 0 0 1.3
15 0 0 3.0
16 2.7
17 0.7
18 1.0
19 0.7
20 0
We may now apply to the results of our efficiency-of-training
tables the method of measuring efficiency which was
mentioned at the end of the preceding chapter as the
index of modifiability (that number of tests after
which no errors occur for at least thirty tests).
By taking the average number of tests for the several
individuals in each of the Tables 42, 43, 44, and
45 we obtain the following expressions of efficiency:—
Two-five-test 81.7 +- 2.7
Ten-test 88.0 +- 4.1
Twenty-test 91.0 +- 5.3
Continuous-test 170.0 +- 4.8
Since the difference between the indices for the ten-test
and the twenty-test methods lies within the limits
of their probable errors (+-4.1 and +-5.3) it is evident
that it is not significant. Except for this, I
think these indices may be accepted as indications
of real differences in the value of the several methods
of training.
A somewhat different interpretation of our results
is suggested by the grouping of individuals according
to sex. In Table 47 appear the general averages
for the males and the females which were tested by
the several methods. The most striking fact exhibited
by this table is that of the high efficiency of the
twenty-test method for the females. Apparently
they profited much more quickly by this method than
by the ten-test method, whereas just the reverse is
true of the males. I present the data of this
table merely to show that general averages may hide
important facts.
EFFICIENCY OF TRAINING
CONDITION MALES
FEMALES
INDEX
OF MODIFIABILITY INDEX OF MODIFIABILITY
2 or 5 tests per day 85.0
80.0 10 tests per day 72.0
104.0 20 tests per day
94.0 88.0 100 or more tests per
day 160.0 180.0
