Measure Your Mind: The Mentimeter and How to Use It — Context and Discussion

ble of meeting and defeating a Teutonic military machine which had come to be known as the most powerful and skillful in the world.

The gravity of the situation forbade experiments with hit-or-miss methods. It was imperative that no round pegs be placed in square holes. Each one of those nearly three million American soldiers had to be placed where he would be of greatest service. Some simple, quick method of distribution was needed. It was perfectly obvious that these men could not be equally good material for soldiers or officers. Out of so great a number it was reasonably certain that men could be found especially qualified to perform each one of the particular tasks which the infinitely complex scheme of organization of a modern army requires.

It was in accordance with the law of probabilities that there would be contained in this mass of soldier material men highly skilled in every one of the more than seven hundred distinct and specific trades and handicrafts in which artisans were needed for the successful maintenance of the fighting forces in the field. The drag-net of the selective service system was certain to gather in its meshes men who were natural leaders and many more men who could only follow. From every city block, every crossroads hamlet, every village street would come those who could teach and those who could only learn. It was inevitable, moreover, that in this huge aggregation of human beings there would be a percentage of the wholly unteachable, the mentally stunted, fit only to be hewers of wood and drawers of water and sure to be a detriment and handicap to any military organization whatsoever.

In a lesser degree the same generalizations applied to the human raw material admitted to the various officers’ training courses; even though a fairly high minimum of educational attainment was required of all candidates, there was bound to be a wide range of military value between the best and the poorest of this officer material.

Psychology, the science that deals with the human mind, offered the only possible short-cut to the ultimate goal of the placement of every individual in the Army at the point where his efficiency would be greatest. The processes of the selective draft had weeded out the larger portion of the physically unfit. The draft questionnaire, as finally revised, provided for a rough preliminary classification of men according to their own estimates of themselves. But something more was needed—some system for passing the entire Army, officers and men, through a series of graduated sieves, as it were, so cunningly devised, and operated with such scientific precision as to tag, label, and index each and every one so exactly that as little as possible would be left for experience to disclose as to his qualifications for his particular part of the Army’s job.

On April 6, 1917, the United States Congress declared the existence of a state of war with Germany. On that same date there was being held in Boston a meeting of a group of psychologists known as the “Experimentalists,” among whom was Dr. Robert M. Yerkes, president of the American Psychological Association. On receipt of news that America was at last at war, all regular business of the meeting was suspended and those present resolved themselves into an informal committee to consider ways and means by which the psychologists of America could best serve their country.

On the evening of that day, as the result of many conferences, the president of the association asked the council to authorize him to appoint committees on various phases of applied psychology for the purpose: first, of enlisting the coöperation of every trained psychologist in America, including the entire membership of the American Psychological Association; and, second, of determining precisely what service the psychologists could best perform. The proposal met with an immediate response and Doctor Yerkes and his committee went to work.

The Army General Staff was skeptical at first, but Doctor Yerkes and his associates overcame this skepticism and by midsummer of 1917 the Division of Psychology of the Medical Department of the United States Army, with Doctor Yerkes at its head with the rank of major, was actively functioning, and the Committee on Classification of Personnel in the Army had been established and was demonstrating, to the surprise of the General Staff and the War Department, the possibility of determining by scientific means the relative military value and proper military assignment of the officers and men of the Army. By the end of 1917 psychology, as applied to war, had so far justified itself that the Surgeon General reported complete success in achieving the desired results, which he stated, concisely, to be: (a) to aid in segregating the mentally incompetent, (b) to classify men according to their mental ability, and (c) to assist in selecting competent men for responsible positions.

The programme of the Division of Psychology of the Medical Department included mental tests for all recruits during a two-weeks detention period. These intelligence ratings, as they were officially termed, aimed to aid:

(1) In the discovery of men whose superior intelligence suggested their consideration for advancement;

(2) In the prompt selection and assignment to development battalions of men who were so inferior mentally that they were suited only for special assignments;

(3) In forming organizations of uniform mental strength where such uniformity was desired;

(4) In forming organizations of superior mental strength where such superiority was demanded by the nature of the work to be performed;

(5) In selecting suitable men for various army duties or for special training in colleges or technical schools;

(6) In the early formation of training groups within a company in order that each man might receive instruction and drill according to his ability to profit thereby;

(7) In the early recognition of slow-thinking minds which might otherwise be mistaken for stubborn or disobedient characters;

(8) In eliminating from the army those men whose low-grade intelligence rendered them either a burden or a menace to the service.

In three systems of tests in use between May 1 and October 1, 1918, in the United States Army, approximately one million three hundred thousand men were tested.

The test first applied to all, men and officers, who could read English, was known as the “Alpha.” This was a group test. It required only fifty minutes and could be given to groups as large as 500. The test material was so arranged that each of its 212 questions might be answered without writing, merely by underlining, crossing out or checking. The papers later were scored by means of stencils, so that nothing was left to the personal judgment of those who did the scoring. The mental rating which resulted therefore was wholly objective.

The “Beta” test was used for foreigners and illiterates. It could be given to groups of from 75 to 200 and required approximately fifty minutes. Success in the Beta test did not depend upon knowledge of English, as the instructions were given entirely by pantomime and demonstration. It measured general intelligence through the use of concrete or picture material instead of the printed language. It also was scored by stencils and yielded an objective rating.

Both the Alpha and the Beta tests were known as Group tests because of the large number of men to whom they could be given simultaneously. Those men who failed in the Group tests were given Individual tests in which the instructions were given by a trained psychologist working with one soldier at a time in a quiet private office. These Individual tests were of two sorts: one for men who understood English, and the other for men without education and frequently without knowledge of the English language. The Individual tests served as a check upon the Group tests which had preceded them. No man was recommended for discharge or for labour battalions until after he had been individually examined by a psychologist who spent from a half hour to an hour and a half with him, attempting to determine whether or not the results of the Group tests could be relied upon.

To determine the relative intelligence of five hundred men in fifty minutes by a method so completely objective that no part of the resulting classification is based on the individual judgment or opinion of either the examiner or any of the men themselves is certainly a practical application of psychological science. Simple as the Alpha test was, its practical working out and reduction to an exact scientific formula was the work of hundreds of highly trained minds for many months. In its concrete application it looks like a children’s game, but the results are so reliable as to be almost uncanny in the precision with which they tally with the conclusions reached in the same cases as a result of long and intimate observation.

(For full details of the Alpha test the reader is referred to Appendix B to this volume.)

The highest score a man could make in the Alpha test was 212. This is an absolutely perfect score, a correct answer or response to every one of the 212 questions or examples; but any man who made a score above 135 was given the highest possible rating, Grade A, in the mental schedule. There were seven ratings in all: A, above 135; B, which included those making 104 to 135; C, _plus_, which took in those down to a score of 75; C, for those scoring from 45 to 74; C, _minus_, for those with scores of 25 to 44; D, for the ones who gave from 15 to 24 correct answers; and D, _minus_, for those who were unable to answer correctly more than 14 out of the 212 questions.

Now for the proof! Here is an official report of one of many comparisons made between the results of the psychological tests and the actual observations and personal knowledge of men by their officers.

The commanding officers of ten different organizations, representing various arms of service in one camp, were asked to designate (a) the most efficient men in their organizations, (b) the men of average value and (c) the men so inferior that they were barely able to perform their duties. The officers had been with these men from six to twelve months and knew them exceptionally well. The total number of men rated was 965, about equally divided between the three classifications.

After the officers’ ratings had been made, the men were given the Alpha test, and the comparison of results showed that the average score recorded in this test by those men the officers had graded as “best” was approximately twice as high as those the officers termed their poorest men. Of men scoring C, _minus_, in the Alpha test, 70 per cent. were those classed by the officers as their poorest men and only 4.4 per cent. of those ranked with the ones whom the officers regarded as best. Of all the men whose scores were above C, _plus_, 55.5 per cent. had been graded by their officers as their best men and only 15 per cent. as among their poorest soldiers.

In another camp 765 men of a regular infantry regiment, who had been with their officers for several months, were graded by their officers in five classes, according to their practical military value. Seventy-six of these men were rated either A or B by the Alpha test; all but nine of these had been graded “one” and “two” by their officers, and none of them had been placed in the lowest grade.

Out of 238 of these soldiers who scored D or D, _minus_, in the psychological test, all but eight had been placed in the three lowest grades by their officers. The psychological ratings and the ratings of the company commanders were identical in 49.5 per cent. of all cases. In 88.4 per cent. of the cases the agreement was within one step, and in only seven tenths of 1 per cent. was there a disagreement between the psychological test results and the officers’ ratings of more than two steps.

Here is another comparison. Sixty company commanders each named his ten best and ten poorest privates. Without any knowledge on the part of the psychological examiners in this or in any other of the comparative tests as to the ratings the officers had given the men, the Alpha gave the grade of D or D, _minus_, to 57.5 per cent. of those picked as the poorest and placed all but a fractional percentage of 1,118 men in the same classes in which they had been placed by their officers on the basis of observation and experience.

Those who failed in the Group tests were given individual attention by the clinical psychologist. The examination here was frequently by the Stanford Revision of the Binet test or by the Yerkes-Bridges Point Scale. For men who could not understand the instructions and the language necessary for taking these two tests a series of specially devised performance tests, consisting chiefly of picture puzzles, cubes, squares, crescents, and other forms cut from wood, were provided. The assumption was that a man who has not intelligence enough to place a triangular block in a perfectly obvious triangular hole, or to piece together the six or seven parts which, when properly assembled, make up the figure of a man or a ship is so hopelessly deficient mentally as to be not only of no value, but a positive detriment to the Army. In many instances fully grown men with the mentality of children seven or eight years old were thus weeded out from among the recruits who had successfully passed the physical tests and been inducted into the service. Men making the D, _minus_, or E score in either the Alpha or the Beta tests were graded as of very inferior intelligence; D, _minus_, men were held to be fit for regular service but the E men were recommended for service in the development battalions or for discharge.

About 15 per cent. of all the soldiers examined were scored in the D class. They were ranked as of inferior intelligence, likely to be fairly good soldiers but slow in learning, short on initiative, requiring more than the usual amount of supervision, and unable to rise above the grade of private. Most D, _minus_, and E men were below the mental age of ten years; few men making a psychological score of D had the intelligence of the average normal fourteen-year-old boy. About 20 per cent. of the 1,500,000 soldiers examined by the psychological method made the score of C, _minus_, which indicated low average intelligence. These men were good soldiers, however, and did satisfactory work in routine matters. The C men, those of average intelligence, included about 25 per cent. of the drafted men and furnished a fair proportion of non-commissioned material.

Those in the C, _plus_, rating, which indicated high average intelligence, included from about 15 to 18 per cent. of all the soldiers examined. This group provided not only a large amount of non-commissioned officer material, but an occasional soldier whose qualities of leadership and power to command fitted him for a commission.

A man who made a score of B in the Alpha test was graded as of superior intelligence. Between 8 and 10 per cent. of all soldiers examined made the B score. This group included a large proportion of men of the commissioned officer type and a very large proportion of men fit for the higher non-commissioned officers’ details.

Only 4 to 5 per cent. of the men in the Army made the score of A in the Alpha test, which means that they were able to answer in the given time, correctly, more than 135 of the 212 questions in the test. These were men of very superior intelligence—indeed, of marked intellectuality. Men of this mental type who had any leadership ability whatsoever made the various grades of commissioned officers.

The practical application of the psychological tests covered a very wide range. The highest intelligence among enlisted men was required in the Field Artillery, Machine-Gun Battalions, and Signal Corps. Men of the lowest grade of intelligence served as labourers, teamsters, and in other non-combatant service, while men only slightly below the average performed the duties of an infantryman satisfactorily.

By the application of the mental tests it was found possible to bring up the average of particular companies, regiments, and detachments, by exchanging men of high mentality from one regiment for an equal number of men of the lower mental grade from another regiment in which the average of ability was low. A great saving of time and energy was made possible by being able to determine that a particular soldier, on the strength of his psychological score, was qualified to become a good artilleryman, machine gunner, or signal-corps man, or what not. If only in preventing the loading up of combatant divisions with men qualified only for the service of supply, the work of the psychologists made possible the elimination of incalculable delay in getting our overseas contingent ready to fight.

The intelligence tests used in the Army were admittedly imperfect at many points. They were especially designed for and adapted to the testing of a very much larger group than is ever likely again to be subjected to any single test or series of tests, and so, for most civilian purposes, these Alpha and Beta tests cannot be taken as a fair or complete system of ascertaining all the facts which mental tests ought to disclose. But at the time and for their particular purpose they functioned admirably, as all persons familiar with the result obtained will concede.

CHAPTER VII PSYCHOLOGICAL TESTS IN EDUCATION

Just as intelligence tests in the Army have developed a new appreciation of the significance of analyses of intelligence as a means of selecting the right man for the right place in the military machine, so have scientifically devised mental tests emphasized the possibilities of more rapid and satisfactory progress in our educational activities.

The application of psychology to the measurement of teaching methods in institutions of learning is of comparatively recent origin. Up to ten years ago we had been able to make very little use of tests for the measurement of intelligence in schools, colleges, and universities. We were fighting blindly, as it were, to overcome the problems which faced us at every turn. We had no concrete guide, for instance, in our efforts to select proper courses of study for children and adults of various mental capacities, nor could we decide upon uniform efforts toward the disposal of such questions as vocational guidance, schoolroom procedure, juvenile delinquency, promotional schemes, retardation of children, and the proper treatment of sub-normal and gifted pupils.

The retardation problem, for example, has become serious. Statistics indicate that from one third to one half of the children in the public schools of the United States fail to advance with the speed expected of them. Ten to 15 per cent. are retarded two years or more. Five to 8 per cent. do not come within three years of the state of development set as a standard. More than 10 per cent. of the $500,000,000 spent every year in this country for school instruction purposes is used for reteaching children what they already have been “taught” but have failed to learn.

Many efforts toward reform have been fruitful but disappointing. The supposition that evils in existing systems could be completely cured by adopting new methods of instruction, altering promotion methods, giving increased attention to children’s health, and adoption of other innovations, was less effective, experiments have shown, than was generally anticipated by educators who put these theories into operation. These reforms were less successful than their authors expected they would be, for the reason that the reformers fell into the error of assuming that, under the right conditions, all children would be equally, or almost equally capable of making satisfactory progress. They failed to take into account the fact that there are more than two classes of school children and that they cannot be graded merely as “feeble-minded” and “normal.” There are all degrees of intelligence, ranging from idiocy on the one hand to genius on the other, and any efforts toward improvement of conditions must be applied with full recognition of such differences.

There are wide differences among normal human beings in mental inheritance and these differences affect to a marked degree the capacity of men, women, and children to profit from instruction. Just as the Army had to allow for differences in mental capacity, so must the schools differentiate courses of study in such a way that each pupil will be allowed to study in a manner that is easy for him, whether that manner be rapid or slow.