X out of Y binary events Entry Nr. 12, by user 1 


Observation: A poll. Out of Y people, X People answer with "Yes" and the rest answers "No". So the observed probability that a person answers "Yes" is X/Y
Question: Based on the observed sample, what are the bounderies within which we expect the real probability that a random person answers "Yes"? 
www.measuringusability.com/wald.htm 
Provides several methods to calculate the confidence intervall. 

R 
In R type: prop.test(x,y) 

Other websites about "X out of Y events" 


faculty.vassar.edu/lowry/binomialX.html 
Javascript application for Binomial Probabilities 



