POISSON'S PROBABILITY SUMMATION 



615 



as examples of the Poisson exponential, in particular those of Mor- 

 tara " and all hut one of those given by Borlkewitsch.'- 



d JO samvA 



1= o 



O CN ^ 



j= II jr 



.2S "O 



•5 "=> 

 a. \o 



F 11 



tn Si 



•?; -5 +^ a 



r U '-' r- 



^ >2 o 



O O lO 

 U-) O '— ' 



e a a 



^1 "Sulle V'ariazione di Frequenza di Alcuni Fenomeni Demografici Rari," by 

 Giorgio Mortara, Annali di Stalislica, Series V, Vol. 4, pp. 5-61, 1912. 



^2 "Das Gesetz der kleinen Zahlen," by L. von Bortkewitsch, Leipzig, 1898. 



