XVIII— XX] 



Introduction 



XXXIX 



Interpolating for <7,. first, 



,• = •5 „<r,.= -05U log x" = 2-0737, 

 r = -6 O 0V = -051-1- log x' = 2-2537. 



Hence for log x~ = 2-1249 : 



•0512 ri , .__ 

 r " = ' O + -1800 [ ' 1] = "° 28 - 

 We conclude that the equiprobable correlation is - 53. 



(4) Imbecility and Deaf-mutism. 



log x" = 3-9039 cr,. = -Ol75, 

 r = 0-95, O o-, = -01 , log x 2 = *3673 ; „°v = "02, log x 2 = 37660. 

 Hence: r = 0'J5, O o-, = -0175, log x 2 = 39163. 



Again : 



r = 090, „ct,. = -01, log x 2 = -i-2207 ; „o-,. = -02, log % 2 = 3-6197. 

 Hence: r-090, <r,. = -0175, log X * = 3-7699. 



Interpolating log x'- = 39039 between 39163 and 37699, we find 



r P = 0-946. 



(5) Developmental Defects and Dullness. 



log x * = 3-5128, o-,= 0201. 

 r = 0-8, <r,. - -02, log X 2 = 3'4097 ; <x,. = 03, log tf = 3-0598. 

 Hence : „o-, = 0201, log X 2 = 3"4062. 



r = 0<), ,«r-"02, log x 2 = 3-6197; O o-,. = -03, log %= = 3-2690. 

 Hence : log tf = 3-6162, for „cr,. = -0201. 

 Thus, by interpolating logx s = 3-5128 between 3'4062 and 3-6162, we find 



r>=-851. 

 We have accordingly the following results : 



It will be seen that equiprobable r P confirms generally the results from P, i.e. 

 the tables for 'Datura' and ' Houses' give no sensible association. r t also confirms 

 this view and shows that ' Houses ' is even lower in the scale than ' Datura.' The 

 order of r P is the same as that of Yule's coefficient of association Q, but neither 

 r r , r t , G lt P or Q support the conclusions stated to flow from the percentages on 



