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Christopher D. Green
York University, Toronto, Ontario
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Joseph Jastrow (1896)
First published in Psychological Review, 3, 68-71.
Posted October 2000
I was pleased to learn by the July number of the PSYCHOLOGICAL REVIEW that my experiments upon mental community had been repeated at Wellesley College; but before reading far in the report of the experiments, my pleasure was changed to regret by finding that the method of experimentation and of computation had been diverged from in essential points. It did not surprise me, therefore, that the results reached were in part different from those published by me. I think it can be readily shown, however, that the Wellesley results do in no serious way tend to invalidate those reached upon Wisconsin students; and that on the one hand in the Wellesley report the contradiction between the two is exaggerated, and on the other the reflections made upon results reached by such statistical methods at Wisconsin or elsewhere are unwarranted.
The first of the two points at issue relates to the ratio of different words found amongst lists of natural associations prepared by groups of men and women students. The lists each contain one hundred words. I had found in 50 such lists prepared by students at the University of Wisconsin, only 2024 different words; among 25 men's lists, 1,375 different words; among 25 women's lists, 1,123 different words; or in percentages, 40.5%, 55.0%, 44.9%.· At Wellesley, although 25 lists prepared by women students were available, only 15 (why this was done is not told) were used in the computation; and because in these 15 lists as many as 1103 different words are found, the results are supposed to antagonize those published by me. But the most essential [p. 69] requisite for the fairness of such a comparison has been neglected, namely, that the number of lists in the two cases shall be the same. I had taken special pains to call attention to this point in a footnote in my first article (New Review, Dec., 1891, p. 562),where it is distinctly stated that the ratio of repetition depends upon the number of persons writing the lists as well as upon other factors; and again, in my second article in an experiment involving a different kind of word association (Educational Review, December 1891, footnote to p. 448), I had shown the general course of the law connecting frequency of repetition with the number of contributors to the word associations. Indeed, the mere fact that as given above the percentage of different words for 100 students is 40·5; while that for the groups of 50 students composing the same 100 it is 55.0% and 44.9% respectively, is a sufficiently obvious indication of the phenomenon in question. It is therefore entirely to be expected that the number of different words in the 15 Wellesley lists will be relatively larger than in either of the 25 Wisconsin lists. The law above referred to demands this. A fair comparison must be between two sets of 15 lists each from Wellesley and Wisconsin, or sets of 25 each from the two colleges. But, further, I do not hesitate to predict that even on the basis of such a comparison the Wellesley words will be found to show a smaller degree of community than the Wisconsin lists, and that because, as I shall attempt to show presently, the words written at Wellesley seem to be less natural and unreflective than those written at Wisconsin; and, as indicated in the note to my first article, the ratio of repetition depends, too, upon the character of the task. I had shown, for instance, that the repetition of words is greatest amongst the first words of each list, where the associations are most spontaneous and natural.
The second point at issue relates to the manner of distribution of the words written by the students, into twenty-five different classes as indicative of the relative prominence of these categories in the masculine and in the feminine mind. The strong preference of the feminine mind for certain concrete and familiar classes of words, in particular for articles of dress, interior furnishings, foods, etc., and the absence of abstract words, which appeared in the Wisconsin lists, entirely fail to appear in the Wellesley lists. The clue to this difference is to be found in the manner in which the lists were prepared. The lists which I used were written as rapidly as possible, and by each student at his or her own home, under as natural surroundings as possible. The Wellesley process is thus described: "That the thought process might be as free as possible, no restriction was made. The [p. 70] students were not even asked, as in the case of Dr. Jastrow's class, to write as rapidly as possible, but this difference in the method cannot possibly be supposed to account for the wide difference in results." Here I must beg to differ; I am of the opinion that it does very largely account for the difference in the results and I am glad to be able to strengthen my opinion by that of Mr. Havelock Ellis, who in his work on "Man and Woman" (pp. 166-170), extensively cites my results. In a card to the Editor of this REVIEW he wrote as follows: "In the July Psychological Review I noticed a record of experiments supposed to invalidate Jastrow's on community of ideas. I am sorry it has not been pointed out that they do nothing of the kind. It is essential that the words should be written as rapidly as possible (the italics are Mr. Ellis's). In this case ample time was given for conscious or unconscious selection. The results showed a difference which might largely have been foretold." The large number of abstract words is one of many indications of the unconscious selection going on in the Wellesley lists, and one list alone contained fifty abstract terms. I lay especial stress in the comparison of masculine and feminine mental traits upon securing as natural a material as possible, and the writing as rapidly as possible is a help toward this result. I remember that in writing my first paper I hesitated between using only the first fifty or the entire one hundred words of each list, feeling that the first half, when the words were natural and spontaneous, was in many respects the more typical. In brief, then, I regard the Wellesley lists as more reflective, less spontaneous than my own and the differences between us as in large measure due to this difference in method.
It remains to add (1) that as above indicated the proportion of different words will be larger when the words are unduly of the remote and abstract kind, so that the difference in method in the two results also goes to account for the higher percentage of different words in the Wellesley lists, and (2) that as I have indicated elsewhere (Educational Review, December 1891), it is only in the unrestricted spontaneous kinds of association that I found community of ideas greater in women than in men, and further that in dealing with such small groups as fifteen or twenty-five persons large room must be allowed for accidental variation. (See PSYCHOLOGICAL REVIEW, Vol. 1., No. 2, pp. 152-158).
I, therefore, see in the Wellesley attempt to corroborate my results nothing that markedly conflicts with the conclusions I drew from my own experiments, and furthermore I find in them a positive contribution [p. 71] in that they show that a difference in methods of experimentation and in the treatment of material will bring about definite and predictable differences in the results reached; and that they thus emphasize the value and reliability of the statistical method, when efficiently applied, in the study of mental phenomena.
MADISON, WIS., October 14, 1895.
 I must explain that the delay in the appearance of the above rejoinder is due to a long illness and resulting accumulation of duties.