6.2 The Binomial distribution

Question 1

How can you model X with a binomial distribution?

Answer 1

» X~B(n,p)
» N is the number of trials
» P is the probability of success

Question 2

What are the 4 points which are needed for a binomial model to be valid?

Answer 2

» There are fixed number of trials,n
» There are 2 possible outcomes
» There is fixed probability of success,p
» The trails are indepedent of each other

Question 3

What is the probability mass function of a random variable which is distributed using B(n,p)?

Answer 3

» P(X = r) = nCr.p^r.(1-p)^n-r

Question 4

What are the 2 edge cases?

Answer 4

» P(X=0) = (1-p)^n
» P(X=n) = p^n

Question 5

How do you answer a question which asks how is X distributed?

Answer 5

» Describe the model interms of X~B(n,p)

Question 6

What is n sometimes called?

Answer 6

» The index

Question 7

What is p sometimes called?

Answer 7

The paramater

Question 8

What is the equation for P(success)?

Answer 8

» p

Question 9

What is the equation for P(Faliure)?

Answer 9

» 1-p

Question 10

What does~ mean?

Answer 10

» Distribution

Question 11

What does~ mean?

Answer 11

» Distribution