Page:The American Journal of Psychology Volume 1.djvu/83

 (i RADIAL PRESSURE CHANGES.

77

In the preceding table the upper horizontal line expresses the initial weight in grammes. The rate of differentiation per second is always T f T of this. The numbers are seconds and fractions of seconds. Of the signs prefixed plus denotes increase of weight and minus decrease, the numbers above with no sign being the average of the two below. Each number is an average, of twenty single experiments. Thus, with an initial weight of five grammes, where the rate of differentiation would be 0.16 grammes per second, it takes Y. M. 22.10 seconds to make up his mind with confidence whether the change of pressure he knows from the signal is taking place, is an increase or a decrease, while J. M. decides in 15.45 seconds.

Table II.

1 6 ITS

tI*

4 T2T

2

T"ST

¥TTT

zmr

H.B.N.

3.28 +3.25 —3.31

7.36 +7.23 —7.50

9.36 +9.23 —9.50

15.29 +14.67 —16.00

20.36 +19.00 —21.83

H.N.

3.70 +3.80 —3.60

5.55 +5.40 —5.70

8.20 +7.90 —8.50

8.15 +7.65 —8.65

12.50 +11.90 —13.10

21.50 +21.33 —21.71

E.H.B.

3.05 +3.10 —3.00

5.40 +5.40 —5.30

7.88 +6.80 —8.70

8.48 +7.66 —9.23

9.96

+ 9.25

—1060

14.68 +14.91 —14.46

j. if.

•

6.45

+4.1 —8.6

11.4

+8.6

—14.6

9.9

+10.2

—9.6

11.7 +11.2 —12.2

21.2 +20.5 —21.9

80. +85. —75.

Y.M.

3.43 +3.44 —3.42

4.58 +4.93 —4.36

8.10 +9.12 —7.10

11.65

+9.88

—12.98

22.76 +21.00 —24.40

34.04 +31.60 —37.80

66.00 +67.00 —65.00

C. H.

4.40 +4.80 —4.00

4.85 +5.10 —4.60

5.25 +5.10 —5.40

5.85 +6.10 —5.60

7.40 +7.10 —7.70

7.60 +8.00 —7.20