136 



CARNEGIE INSTITUTION OF WASHINGTON. 



STUDIES ON HUMAN GENETICS. 

 Heredity in Aristogenic Families. 



Dr. Howard J. Banker has made a preliminary study on heredity of 

 general intellectual ability as measured by collegiate standing. He 

 reports as follows: 



"The material consisted of the scholarship records of approximately 1,000 

 students of Harvard College, covering a period of 66 years. These individual 

 records were selected primarily with reference to the relationship of father 

 and son and incidentally also with reference to fraternal relationship. As 

 the records covered a long period during which the methods of recording a 

 student's scholarship standing had undergone great changes, it became 

 necessary, for the purpose of comparison, to reduce the gradings to a uniform 

 system. It was a question, therefore, whether from the original records 

 themselves, or in the transformation of these records to a uniform system, 

 there had been introduced such irregularities as to make the records incom- 

 parable. 



"The first test was to plot a frequency distribution of the average grade of 

 each student on a scale of 5 divided into tenths, making 40 classes, with 1 as 

 the highest grade and 5 as the lowest. The distribution was determined, 

 first, for the entire period of 66 years, also for three subperiods of 22 years 

 each, and finally for two subperiods of 40 and 25 years respectively, the for- 

 mer covering the period of chiefly paternal grades and the latter the period of 

 chiefly filial grades, the object being to compare these different periods for 

 any marked variations. 



"The resulting curves showed close approximation in one-third of the 

 highest grades and in one-seventh of the lowest. In the intermediate one-half 

 they diverged considerably, but in such uniform fashion as to indicate the 

 operation of some fundamental law and not as the expression of any hap- 

 hazard irregularity. Table 7 gives the principal constants for the curves 

 for the three subperiods of 22 years. 



"These results encouraged further statistical use of the data and a study 

 was made of the correlation between fathers and children^ as to their general 

 averages in all subjects. Various methods were employed, as the object 

 was chiefly to test the value of the data in statistical work. Table 8 fur- 

 nishes an interesting comparison with a study made by Schuster and Elderton 

 on Oxford students."^ 



Table 7. 



-Constants of polygon of frequency of scholarship grades at Harvard College for the 

 given periods, a, Standard deviation. 



"The Oxford material, which included 2,459 sons, was classified by Schuster 

 and Elderton into six groups according to standing at graduation, as follows: 

 first, second, third, and fourth honors, passed, and no degree. The Harvard 



^A very few girls were included in the data. 



^Schuster and Elderton. The inheritance of ability, being a statistical study of the Oxford 

 class lists and the school lists of Harrow and Charterhouse. Eugenics Laboratory Memoirs, I. 

 London, 1907. 



