Pearl, Intelligence and Size of Head. 



TABLE II. 



193 



The raw material is given in detail in Tables I and II, which 

 are copies of Tables IV and V of the original memoir. In Table 

 II the observed frequencies are given in italic type: the 

 ordinary figures in each compartment of the table give the pro- 

 portionate frequency which should fall in that compartment on 

 the basis of independent probability (r/. infra.). 



In dealing with this material I first applied the contingency 

 method' to Table II as it stands. It was apparent as soon as the 



'Pearson, K. Mathematical Contributions to the Theory of Evolution. XIII. On the Theory 

 of Contingency and its Relation to Association and Normal Correlation. Drapers' Company 

 Research Memoirs, Biometric Series, I., pp. I-35, 2 pi., 1904. 



