ASSORTATIVE MATING IN MEN 481 



— 1 to -|- 1. In this case, the correlation is 4~ •'^^f or about three 

 fourths of the distance up the scale of to 1, from no resemblance to 

 perfect identity. ^^ 



To determine whether men and women tend to parity or disparity 

 in matrimonial choice, we must, therefore, take a large number of mated 

 pairs at random from the general population, sort them into groups 

 according to some characteristic — quantitatively measurable whenever 

 possible — and determine by means of the statistician's coefficient of 

 correlation whether generally similar or dissimilar groups of men and 

 women tend to mate, and how strong this tendency to parity or disparity 

 is. Throughout this paper the intensity of assortative mating will be 

 expressed by the coefficient of correlation. The reader will have to bear 

 in mind merely that positive coefficients indicate a similarity and nega- 

 tive coefficients dissimilarity in husbands and wives as compared with 

 random pairs of men and women from the population, 



II. Assortative Mating for Physical Characters 



1. Stature 



The psychological basis of the popular notion that men and women 

 seek disparity rather than parity in the stature of their mates is not far 

 to seek. On the streets the linear wife and spherical husband, or the 

 reverse combination, appeal to our sense of humor while the multitude 

 of similarities pass unnoticed. Yet when lumped on the statistical 

 scales the modal multitude may outweigh the extreme combinations 

 whose incongruity provoke a smile as they pass to the front circle after 

 the curtain has gone up. 



With the rough statistical methods then available, Galton" was 

 unable to detect any tendency towards marriage selection with respect to 

 stature, but Pearson^^ on the same data as early as 1897 suspected 

 homogamy. The results from his own more extensive family records are 

 shown in Table II. ^*' For convenience the figures for forearm and 

 span are also given. 



^' This value is perhaps a little too high. However much popular opinion 

 may overestimate women 's reticence concerning their ages, statisticians know 

 that even the correct age of marriage of both men and women is hard to obtain. 

 Especial difficulty is to be expected near the extremes of the series. Those 

 embarrassed by years may declare themselves of legal age, or even deduct a few 

 years. Those who are not yet of legal age may falsify to obtain a license. Aa 

 Lutz aptly remarks, these figures, "instead of telling the exact truth, show us 

 the state of things modified somewhat by man's idea of how he thinks they had 

 better be." 



"Galton, F., "Natural Inheritance," p. 206. 



"Pearson, K., Phil. Trans. Boy. Soc. Lond., A, Vol. 187, p. 273, 1897; also, 

 "Grammar of Science," 2d ed., pp. 429-431, 1900. 



^° Pearson, K., and A. Lee, "On the Laws of Inheritance in Man. I., Inherit- 

 ance of Physical Characters," Biometrika, Vol. 2, pp. 372-377, 1903. 



VOL. LXXX. — 32. 



