As described on page 145, the subject was required to mark in each line of 10 numbers every combination of 2 successive digits which added together equaled 11. In correcting the records, three things were noted: (1) the number of combinations found and correctly marked in that part of the material which the subject was able to cover in 5 minutes; (2) the number passed over unmarked by the subject;and (3) the number of incorrect combinations marked. It will be recalled that the same amount of new material was provided the subjects at each test, the quantity having been from the first experiment made large enough so that no subject would be likely to complete the material efficiently in the 5-minute period allowed. Each man began at the first of the blank and proceeded as far as he could within the time limit. In succeeding trials, as the men gained in proficiency and became thoroughly familiar with the number combinations to be marked, they covered more and more of the material provided. It is therefore clear that the sum for combinations marked and combinations passed unmarked (errors of omission) will not be the same from day to day but is a measure of the amount of material covered and depends upon the speed and accuracy of each subject. Tables 151 and 152 give the individual data for all the subjects of Squads A and B. The tables are arranged in the usual form, with the dates in chronological order at the left, and column headings giving the subjects in order. The breaks discussed on page 557 likewise occur in these data. Incorrect combinations were marked by members of either squad in only a few instances, as with Can.1 Some of the desired number combinations were always passed over in the material which was covered. The best records in this respect are those for Gar, September 29; Spe, October 27; and Bro, February 2, when in each case there were two errors of this sort. Lon, Sne, Tho, and Wil, all of Squad B, made individual records with as small a number as 3 errors of omission. The low-diet averages for Squad A show in number of combinations correctly marked a range from 52.92 in the case of Moy to 98.3 for Gul. The averages for combinations missed range from 6.0 for Bro to 44.2 for Gul. The latter usually missed many of the combinations; on January 12 his omissions were 82. The low-diet average for the group of 10 men is 73.2 combinations checked, 17.5 combinations missed; the number wrongly checked is negligible.

Table 151. - Squad A - Cancellation Of Specified Number Groups

Date and number groups.

Bro.

Can.

Kon.

Gar.

Gul.

Mon.

Moy.

Pea.

Pec.

Spe.

Tom.

Vea.

Fre.

Av.1

1917.

Sept. 20:

Found...

28

26

23

27

47

37

25

48

25

10

40

44

34

34.7

Missed...

8

17

5

2

30

19

4

16

15

5

4

20

10

13.5

Mistakes.......

0

0

0

1

1

0

0

0

0

2

1

0

0

.3

Oct. 13:

Found..

56

39

....

40

76

65

43

63

45

30

50

72

50

54.0

Missed...

14

26

51

64

20

10

26

28

0

20

16

20

27.5

Mistakes.......

0

4

3

0

0

2

0

0

0

2

0

0

1.1

Oct. 27:

Found..

68

40

44

60

89

68

51

80

61

30

47

78

..

65.1

Missed..

12

7

15

11

50

13

8

25

26

2

7

10

..

16 0

Mistakes.......

0

1

0

0

0

0

1

0

0

0

0

0

..

.2

Nov. 10:

Found..

65

60

56

62

77

78

43

88

55

33

53

84

..

66.5

Missed............

6

12

5

6

28

9

14

14

27

10

10

21

..

14.7

Mistakes.....

0

4

0

0

0

0

0

0

0

0

0

0

..

.4

Nov. 24:

Found..

75

65

62

67

96

73

41

91

62

34

56

100

..

72.6

Missed..

3

13

3

10

62

25

26

8

22

4

11

6

..

18.6

Mistakes.......

0

3

0

0

0

0

1

0

0

0

2

0

...

.6

Dec. 8:

Found..

81

71

65

67

121

72

50

82

70

45

60

85

...

76.8

Missed..

5

15

7

10

24

30

11

7

17

0

12

4

..

13.5

Mistakes.......

0

1

0

0

0

0

0

0

0

0

0

0

...

.1

Dec. 10:

Found..

80

70

68

72

113

75

54

80

68

..

60

98

.

77 0

Missed...

4

7

4

14

20

21

24

18

20

.

13

6

..

15.6

Mistakes.......

0

0

0

0

0

0

0

0

0

...

0

0

...

0

1918.

Jan. 12:

Found..

70

69

66

72

76

71

56

76

61

..

60

107

.

72 7

Missed...............

4

13

5

7

82

37

14

13

23

..

14

11

..

21.8

Mistakes.....

0

0

0

0

0

0

0

0

0

..

0

0

...

0

Jan. 26:

Found..

80

75

72

75

110

77

58

101

68

..

65

106

..

83.3

Missed...............

4

14

12

9

34

22

14

8

10

..

22

13

..

15.0

Mistakes.....

0

0

0

0

0

0

0

0

0

..

0

0

....

0

Feb. 2:

Found....

08

71

77

70

118

83

71

106

74

..

75

115

..

89 0

Missed..............

2

14

4

7

25

22

10

16

17

.

17

4

..

13.4

Mistakes..........

0

0

0

0

0

0

0

0

0

...

0

0

..

0

Low-diet av.:

76.8

63.2

83.8

66.0

98.3

73.6

52.0

86.2

62 7

36.2

58.4

03.0

50

73.2

Missed............

6.0

13.4

6.0

13 0

44 2

22 1

14 6

15.0

22.1

6 8

14 0

10 1

.,,

17.5

Mistakes..........

0

1.4

0

.3

0

0

.4

0

0

0

.4

0

0

.3

1These averages do not include the records for Aon, Spe, and Fre.

Squad B (see table 152) for the average of normal experiments show a range for combinations checked of 31.8 to 64.8 with Mac and Van, respectively. For combinations missed they show an average of 5.5 to 30.63, with Tho and How, respectively. Their normal group averages are 52.3 and 14.0. The low-diet group averages of the same squad are 67.4 and 12.7, indicating improvement during the reduced diet.

For purposes of comparison, it is desirable to state the results in one figure which will stand as a combination of speed and accuracy. The subjects worked with a time limit, and equal stress was laid on checking the largest number of combinations, and also on going over the material without missing any combinations. The latter was frequently called to the subject's attention first to give it prominence; still it is likely that the matter of speed was more prominent in the thoughts of the subject. In computing the combination value, which is given in tables 153 and 154, a credit of +1 was allowed for each correct number combination found and checked. A demerit of - 0.5 was subtracted for every error of omission and for every wrong combination checked. On this basis the scores range from 6.5 (Spe, September 29) to 113 (Tea, February 2) with Squad A and from - 6.5 (Sch, January 19) to 99 (Van, January 27) in the case of Squad B. In Squad A of the 10 men for whom there are complete records the best number-cancellation scores were made by Vea, Pea, Gul, and Bro. These low-diet averages, as seen in the lower line of table 153, are respectively: 88.8, 78.7, 76.2 and 73.8. With the exception of Gar, all of the subjects improved on their first low-diet date, although Moy and Tom did but very little better on October 13 than they had on September 29. Throughout the whole experiment each individual improved quite regularly in the performance of his test. Gul shows a marked drop in his score for January 12, with a surprising number of omissions, which were more than the correct combinations checked. On the two previous dates his score was about 100 and on the two succeeding dates it was above 100. Two other subjects, Mon and Pec, were also lower on January 12, the first session following the Christmas vacation. Almost a month had elapsed since the preceding experiment; moreover the men were undergoing a very considerable reduction in diet at this time.

1 Can frequently complained of his eyes during these tests. Part of the time he wore an eye-shield during the group experiment. He complained that the light was too strong and he frequently said in the evening that he had a headache. He was asked repeatedly to have his eyes re-examined by a good specialist.

2 Spe, who did not have so much practice as the others, had a lower average, i. e., 36.2.

3 The data for Sch are too fragmentary for comparison.

Table 152. - Squad B - Cancellation Of Specified Number Groups

Date and number groups.

Fia.

Har.

How.

Ham.

McM.

Kim.

Lon.

Mac.

Sch.

Liv.

Sne.

Tho.

Van.

Wil.

Av.1

1917.

Oct. 6:

Found...

22

23

24

21

..

..

27

21

..

17

22

25

29

33

24.3

Missed.......

24

7

25

30

..

..

3

27

..

14

8

3

13

3

13.0

Mistakes.....

0

0

0

0

..

..

0

0

..

1

2

0

0

1

.4

Nov. 3:

Found...

42

47

48

53

34

. ■ > <

58

29

..

45

44

46

61

62

50.6

Missed.......

28

7

40

14

20

....

13

27

.

4

17

9

10

8

15.0

Mistakes.....

0

0

1

0

0

....

1

0

...

0

0

1

0

0

.3

Nov. 17:

Found.......

52

56

58

61

45

..

56

36

..

52

65

54

69

72

59.5

Missed.......

20

10

29

5

21

....

17

34

..

6

16

6

12

8

12.9

Mistakes.....

0

0

0

0

0

..

0

0

..

0

0

0

0

0

0

Dec. 15:

Found...

..

57

55

57

40

.

60

41

..

61

55

59

80

69

61.4

Missed.......

..

9

29

13

29

..

12

28

.

11

16

4

25

11

14.4

Mistakes.....

..

0

0

1

1

..

0

1

..

0

0

0

0

0

.1

1918.

Jan. 5:

Found.......

51

64

64

56

46

35

..

..

40

63

67

..

85

74

65.5

Missed.......

17

13

30

12

28

13

..

.

59

6

9

..

24

5

14.5

Mistakes.....

0

0

0

1

0

1

..

..

0

2

0

..

0

0

.4

Normal av.:

Found...

40.5

49.4

49.8

49.6

41.3

35.0

50.3

31.8

40.0

47 6

50.6

46.0

64 8

62.0

52.3

Missed.......

22.3

9.2

30.6

14.8

24.5

13.0

11.3

29.0

59.0

8.2

13.2

5.5

16.8

7.0

14.0

Mistakes.....

0

0

.2

.4

.3

1.0

.3

.3

0

.6

.4

.3

0

.2

.2

Jan. 13:

Found...

53

71

66

71

..

47

59

..

41

64

63

57

89

68

66.1

Missed.......

13

14

22

6

..

11

12

..

47

9

8

9

20

11

12 4

Mistakes.....

0

0

0

0

..

0

0

..

0

0

0

1

0

0

.1

Jan. 19:

Found...

53

74

59

61

..

49

66

...

33

68

66

53

80

74

65.4

Missed.......

9

14

29

13

..

10

6

..

79

4

22

9

16

14

13.6

Mistakes.....

1

0

0

0

..

0

0

..

0

0

0

0

0

0

.1

Jan. 27:

Found...

59

86

58

65

..

55

67

..

60

76

55

61

104

75

70.6

Missed.......

12

18

32

14

..

19

4

..

90

7

3

11

10

11

12.2

Mistakes

0

0

0

0

..

0

0

..

2

0

0

0

0

0

0

Low-diet av.:

Found...

55 0

77 0

61 0

65 7

..

50.3

64 0

..

44 7

69 3

61 3

57 0

71 0

72 3

67.4

Missed.......

11.3

15.3

27.7

11.0

..

13.3

7.3

..

72.0

6 7

11 0

9.7

15.3

12.0

12.7

Mistakes

.3

0

0

0

....

0

0

..

0

0

0

.3

0

.3

.07

1These averages do not include the records of McM, Kim, Mac, and Sch.

The average for the 10 regular subjects of Squad A (see right-hand column of table 153) shows a rapid and uninterrupted improvement except on January 12.

Squad B, table 154, shows the same general result with this test. In the five normal experiments all the subjects improved regularly, with the exception of a small relapse on the part of some subjects, for example, How, Ham, McM, Sne and Wil on December 15. In the normal averages Wil and Van lead with scores of 58.4 and 55.4, respec-tively. Several subjects have scores of 40 and above. These in order of rank would be Har, Lon, Sne, Liv, Ham, and Tho. In the low-diet period each subject for whom records are complete shows an average above his normal. In the case of Sch, who only had one normal experiment (January 5) there was no improvement and, in fact, a slight decrement during the reduction period. This subject omitted a large number. (See record for January 27.) In the low-diet period the highest average was that of Van, 83.3, an increase of 27.9 over his normal average. Two other subjects, Har and Liv, made increases above 20, but on the average the improvement during the 3 weeks of the reduced diet was small, there being hardly any on January 13 and 19.