1) Large # of trials; n>100
Small probability of success; np<10
2) An observed probability of success over a given time period; Num of fish/hour
λ = Mean P(r) = number of success over a given time period
(e )∗(λ) r
r = # of successes over same time period
NOTE: λ and r have same time period
Ex: Police officer observed that on average, he stops 0.7 people per hour.
λ = 0.7ppl/1hr
What are the probability in a 8hr shift?
λ = (0.7ppl/1hr)(8hrs/8hrs)
- 5.6 r