Lesson 3 Notes STAT 200

3 Pages
84 Views
Unlock Document

Department
Statistics
Course
STAT 200
Professor
Mengzhao Gao
Semester
Spring

Description
STAT 200 Elementary Statistics Lesson 3: Probability  The notation P(A) represents “Probability even A occurs  The notation P(A^c) represents “The probability that the complement of even A occurs”  The complement of an event is simply any event that is not event A  General probability rules: 1. The probability of an impossible event is zero; the probability of a certain event is ≤ one. Therefore, for any even A, the range of possible probabilities is: 0 P(A) ≤ 1 2. For S the sample space of all possibilities, P(S) =1. The sum of all the probabilities for all possible events is equal to 1. 3. For any even A, P(A^c) = 1 – P(A). P(A) = 1- P(A^c) 4. (Addition rule) – this is the probability that either one or both events occur a. If two events, say A and B, are mutually exclusive- that is A and B have no outcomes in common, then P(A or B) = P(A) + P(B) – P(A and B) b. If two events are NOT mutually exclusive, the P(A or B) = P(A) + P(B) – P(A and B) 5. (Multiplication rule) – this is the probability that both events occur a. P(A and B) = P(A) x P(B|A) or P(B) × P(A|B) The straight line symbol does not mean divided. It means “conditional” or “given” b. If A and B are independent, neither even influences or affects the probability that the other even occurs. - then P(A and B) = P(A) × P(B) . This particular rule extends to more than two independent events. For example,
More Less

Related notes for STAT 200

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit