KEMAEKS ON THE METHOD OF CALCULATION ^ 

 PEOPOSED BY ME H. L. TEACHTENBEEG FOE 

 DIALLEL CEOSSINGS. 



By KIRSTINE SMITH, D.Sc. 



From a mathematical or statistical point of view it may be argued 

 that an arbitrary assumption about the generative value of one of the 

 parents is formally unsatisfactory, although one must admit, consider- 

 ing the nature of generative values, which have no natural zero point, 

 that in reality it is of absolutely no consequence. 



The remedy proposed by Mr Trachtenberg, however, seems to hie 

 worse than this slight lack of form. While professing to avoid an 

 arbitrary assumption it appears that the author only replaces it by an 

 unmaintainable assumption. He does not seem to notice that in 

 supposing that the personal values of parents represent their generative 

 values with the same degree of accuracy as that with which the generative 

 value of a group of offspring is observed from a single of its individuals 

 he really makes a new assumption and, as we shall see, a wrong assump- 

 tion. To realise this we only need to look at Mr Trachtenberg's results 

 comparing personal and generative values for parents and offspring, 

 from which I have calculated the following diflferences and their 

 squares : 



Parents 



Offspring 



Total ^012 



Mean value of dj^ ■ 0^0010 



1 " The Analysis of the results of Professor Johannes Schmidt's diallel crossings with 

 trout." By H. L. Trachtenberg, B.A., in Journal of Genetics, Vol. xi. No. 1, 1921, pp 75—78. 



