INFLUENCE OF ORDER OF BIRTH, ETC. 301 
excellent work on The English Convict it is claimed that crimi- 
nality develops in the first born to a much greater extent than it 
does in the later born members of the stock from which the crim- 
inals are derived. Pearson confirms the deductions of Heron and 
Goring for insanity and criminality, and he has adduced data to 
show that the first born are unusually liable to albinism, imbecil- 
ity. epilepsy and cataract. 
A number of writers have attacked the findings of Pearson 
and his colleagues on the ground that they are based upon a 
statistical fallacy. Greenwood and Yule have arrived at a quite 
different ordinal distribution of the relative number of individuals 
in the members of the families of the marked individuals. When 
we are dealing with cases of insanity or tuberculosis in which we 
start with individuals, say in institutions, it is obvious that all 
members of the marked person’s family are not equally apt to be 
found in the segregated class. There is an age at which insanity 
and tuberculosis is more than likely to appear and the chances are 
decidedly against two persons from the same family being con- 
fined at the same time, there being an especially strong bias 
against the members who have not reached adult life. Recently 
Pearson’s methods have been attacked by Dublin and Langham 
of the Statistical Bureau of the Metropolitan Life Insurance 
Company of New York. These authors contend that Pearson’s 
method “‘is based unequivocally on the assumption that the 
distribution according to order of birth of the pathologic com- 
munity from which his ‘marked’ or affected subjects are ob- 
tained is identical with the distribution of the sibships of these 
subjects. For if that be the case he can use the distribution of 
the sibships of the affected as a norm in comparing with it the 
distribution of the affected, in the effort to show that actually 
the early born among his subjects preponderate beyond all ex- 
pected proportions. We shall endeavor to show that, when there 
is no weighing according to order of birth among the individuals 
affected, the distribution of the affected or that of the pathologi- 
cal community represented by them is not in any case compar- 
able with that of their sibships. We propose to take the distri- 
