A quick question! The number of episodes per year of otitis media follows a Possion distribution with lambda = 1.6 episodes per year. Wouldn't the probability of getting 3 or more episodes of otitis media in the first 2 years of life be: > ppois(q=3, lambda=1.6*2, lower.tail = TRUE, log.p = FALSE) [1] 0.6025197 I am confused with the lambda and 3 or more.. thx much