Sixteen Experimental Investigations from the Harvard Psychological Laboratory by Hugo Münsterberg (good novels to read in english TXT) 📖

three-letter, one four-letter, one five-letter, and one

six-letter nonsense word. The position in the series occupied by each

kind was constantly varied. In all other respects the same principles

were followed in constructing the B set as were observed in the A

set with the following substitutions:

 

No two foreign symbols of a series and no two terms of a couplet

contained the same sounded vowel in accented syllables.

 

The rule for the avoidance of alliteration, rhyme, and assonance was

extended to the foreign symbols, and to the two terms of a couplet.

 

The English pronounciation was used in the nonsense words. The

subjects were not informed what the nonsense words were. They were

called foreign words.

 

Free body movements were used in the movement series as in the A

set. Rarely an object was involved, e.g., the table on which the

subject wrote. The movements were demonstrated to the subject in

advance of learning, as in the A set.

 

The following are typical B series:

 

B2. Nonsense words and objects.

 

quaro rudv xem lihkez

lid cent starch thorn

 

B3. Nonsense words and verbs.

 

dalbva fomso bloi kyvi

poke limp hug eat

 

B4. Nonsense words and movements.

 

ohv wecolu uxpa haymj

gnash cross frown twist

 

The time conditions for presenting a series remained practically the

same. In learning, the series was shown three times as before. The

interval between learning and testing was shortened to 4 seconds, and

in the test the post-term interval of A^{13-16} retained (6 secs.).

This allowed the subject 9 secs. for recalling and writing each term.

The only important change was an extension of the number of tests from

two to four. The third test was one week after the second, and the

fourth one week after the third. In these tests the familiar word was

always the term required, as in A^{1-4}, on account of the

difficulty of dealing statistically with the nonsense words. The

intervals for testing permanence in the B set may be most easily

understood by giving the time record of one subject.

 

TIME RECORD OF Hu.

 

Series. Im. Rec. Two Days. Nine Days. Sixteen Days.

B^{1-4} Feb. 12 Feb. 14 Feb. 21 Feb. 28

B^{5-8} Feb. 19 Feb. 21 Feb. 28 Mch. 7

B^{9-12} Feb. 26 Feb. 28 Mch. 7 Mch. 14

B^{13-16} Mch. 5 Mch. 7 Mch. 14 Mch. 21

 

The two half-hours in a week during which all the work of one subject

was done fell on approximately the same part of the day. When a number

of groups of 4 series each were to be tested on a given day they were

taken in the order of their recency of learning. Thus on March 7 the

order for Hu was B^{13-16}, B^{9-12}, B^{5-8}.

 

Henceforth there was also rotation within a given four series. As

there were always sixteen series in a set, the effects of practice and

fatigue within a given half-hour were thus eliminated.

 

In the following table the results of the B set are given. Its

arrangement is the same as in Table 1., except that the figures

indicate the number of absent terms correctly recalled out of four

couplets instead of seven or five. Where blanks occur, the series was

discontinued on account of lack of recall. As in Table 1., the tables

in the first, third and fifth columns show successive stages of the

same series. Immediate recall is omitted because with rare exceptions

it was perfect, the test being given merely as an aid in learning.

 

TABLE II.

 

SHOWING RECALL AFTER TWO, NINE, AND SIXTEEN DAYS.

 

Days. Two. Nine. Sixteen. Two. Nine. Sixteen.

N. O. N. O. N. O. V. M. V. M. V. M.

Series. M.

B^{1-4} 2(1) 4 1(1) 2 1(1) 2 4 4 4 2 4 2

B^{5-8} 3 1 2 1 1 1 2 2 2 1 1 1

B^{9-12} 2 3 0 3 0 2 3 2 2 0 2 2

B^{13-16} 2(1) 3 2(1) 0 2(1) 0 1 2 1 0 1 0

Total 9(2) 11 5(2) 6 4(2) 5 10 10 9 3 8 5

Per cent. 64 69 36 38 29 31 63 63 56 19 50 31

 

S.

B^{1-4}¹ 0 2 0 0 0 1 0 1

B^{5-8} 0 0 0 0

B^{9-12}¹ 0 1 0 0 0 1 0 0

B^{13-16}² 0(2) 1 0(2) 1 0(2) 1 0 0(1) 0 0(1) 0 0(1)

Total 0(2) 4 0(2) 1 0(2) 1 0 2(1) 0 1(1) 0 0(1)

Per cent. 0 25 0 6 0 6 0 13 0 7 0 0

 

Hu.

B^{1-4} 1(1) 4 0(1) 1 0(1) 2 1 3 0 2 0 0

B^{5-8} 0 1(1) 0 0(1) 0 0(1) 0 1 0 1 0 1

B^{9-12} 0 1 0 0 0 1 0 0 0 1 0 0

B^{13-16} 0(1) 0 0(1) 0 0(1) 0 0 4 0 0 0 0

Total 1(2) 6(1) 0(2) 1(1) 0(2) 3(1) 1 8 0 4 0 1

Per cent. 7 40 0 7 0 20 6 50 0 25 0 6

 

B.

B^{1-4} 1 1(1) 0 0 0 0(1) 0 0

B^{6-8} 1 2 1 2 1 1 1 0 1 0 1 0

B^{9-12} 0 2(1) 0 0(1) 0 0(1) 0(1) 2 0 2 0 1

B^{13-16} 1 3 1 1 1 1 1 2 0 1 0 1

Total 3 8(2) 2 3(1) 2 2(1) 2(1) 4(1) 1 3 1 2

Per cent. 19 57 13 21 13 13 13 27 7 20 7 13

 

Ho.

B^{1-4}¹ 3 2(1) 2 2(1) 1 0(1) 1(2) 1(2) 1(2) 0(2) 0(2) 0(2)

B^{6-8} 1 1(1) 1 0(1) 1 0 0 1(1) 1 1 0 1

B^{9-12} 0(1) 1 0(1) 1 0(1) 0 1 1 1 1 0 0

B^{13-16}³ 0 0 0 0 0 0 0(1) 4 0(1) 2 0(1) 0

Total 4(1) 4(2) 3(1) 3(2) 2(1) 0(1) 2(3) 7(3) 3(3) 4(2) 0(3) 1(2)

Percent. 33 30 25 23 17 0 17 58 25 33 0 8

 

Mo.

B^{1-4} 3 3 3 1 4 1 0 2 0 2 0 2

B^{5-8} 1 4 1 1 1 2 1 2(2) 1 1(2) 1 1(2)

B^{9-12} 2 4 2 4 1 4 0(1) 3(1) 1(1) 3(1) 1(1) 2

B^{13-16} 2(2) 4 2(2) 4 2(2) 2 1 4 1 4 1 4

Total 8(2) 15 8(2) 10 8(2) 9 2(1) 11(3) 3(1) 10(3) 3(1) 9(2)

Percent. 57 94 57 63 57 56 13 85 20 79 20 69

 

¹Four presentations in learning.

²Five presentations in learning.

³Five days’ interval instead of two.

 

In the following summary the recall after two days is combined from

Tables I. and II. for the three subjects M, S and Hu, there

being no important difference in the conditions of experimentation.

For the three other subjects this summary is merely a résumé of Table

II. The recall after nine and sixteen days in Table II. is omitted,

and will be taken up later. The figures are in all cases based on the

remainders left after those couplets in which indirect associations

occurred were eliminated both from the total number of couplets

learned and from the total number correctly recalled. E.g., in the

case of nouns, M learned, in all, 42 couplets in the A and B

sets, but since in 3 of them indirect associations occurred, only 39

couplets are left, of which 21 were correctly recalled. This gives 54

per cent.

 

SUMMARY OF RECALL AFTER TWO DAYS.—FROM TABLES I. AND II.

 

N. O. V. M.

M. 54 per cent. 62 per cent. 63 per cent. 61 per cent.

S. 8 ” 21 ” 7 ” 12 “

Hu. 11 ” 30 ” 5 ” 59 “

B. 19 ” 57 ” 13 ” 27 “

Ho. 33 ” 30 ” 17 ” 58 “

Mo. 57 ” 94 ” 13 ” 85 “

Av. 30 per cent. 49 per cent. 20 per cent. 50 per cent.

 

Av. gain in object couplets, 19 per cent.

” ” ” movement couplets, 30 per cent.

 

The first question which occurs in examining the foregoing tables is

concerning the method of treating the indirect associations, i.e.,

obtaining the per cents. The number of couplets correctly recalled may

be divided into two classes: those in which indirect associations did

not occur, and those in which they did occur. Those in which they did

not occur furnish us exactly what we want, for they are results which

are entirely free from indirect associations. In them, therefore, a

comparison can be made between series using objects and activities and

others using images. On the other hand, those correctly recalled

couplets in which indirect associations did occur are not for our

purposes pure material, for they contain not only the object-image

factor but the indirect association factor also. The solution is to

eliminate these latter couplets, i.e., subtract them both from the

number correctly recalled and from the total number of couplets in the

set for a given subject. By so doing and by dividing the first

remainder by the second the per cents, in the tables were obtained.

There is one exception to this treatment. The few couplets in which

indirect associations occurred but which were nevertheless

incorrectly recalled are subtracted only from the total number of

couplets in the set.

 

The method by which the occurrence of indirect associations was

recorded has been already described. It is considered entirely

trustworthy. There is usually little doubt in the mind of a subject

who comprehends what is meant by an indirect association whether or

not such were present in the particular series which has just been

learned. If none occurred in it the subjects always recorded the fact.

That an indirect association should occasionally be present on one day

and absent on a subsequent one is not strange. That a second term

should effect a union between a first and third and thereafter

disappear from consciousness is not an uncommon phenomenon of

association. There were thirteen such cases out of sixty-eight

indirect associations in the A, B and C sets. In the tables they

are given as present because their effects are present. When the

reverse was the case, namely, when an indirect association occurred on

the second, ninth or sixteenth day for the first time, it aided in

later recall and was counted thereafter. There were eight such cases

among the sixty-eight indirect associations.

 

Is it possible that the occurrence of indirect associations in,

e.g., two of the four couplets of a series renders the retention of

the other two easier? This could only be so when the intervals between

two couplets in learning were used for review, but such was never the

case. The subjects were required to fill such intervals with

repetitions of the preceding couplet only.

 

The elimination of the indirect association couplets and the

acceptance of the remainders as fair portrayals of the influence of

objects and movements on recall is therefore a much nearer approach to

truth than would be the retention of the indirectly associated

couplets.

 

The following conclusions deal with recall after two days only. The

recall after longer intervals will be discussed after Table III.

 

The summary from Tables I. and II. shows that when objects and nouns

are coupled each with a foreign symbol, four of the six subjects

recall real objects better than images of objects, while two, M and

Ho, show little or no preference. The summary also shows that when

body movements and verbs are coupled each with a foreign symbol, five

of the six subjects recall actual movements better than images of

movements,