Editorial note — Page 186 CHAPTER IX
Reading edition
[Footnote 1: These facts are based on the reports of Karl Pearson in his On the Laws of Inheritance in Man. What is meant by coefficient of correlation may be explained as follows: If the coefficient of correlation between father and son is .3 and the coefficient of correlation between brother and brother is .5 we may say: a son on the average deviates from the general trend of the population by .3 of the amount of his father's deviation, a brother by .5 of the amount of his brother.]