Lecture 17 conditional probability

Slides:



Advertisements
Similar presentations
Probability Presented by Tutorial Services The Math Center.
Advertisements

PROBABILITY: Combining Two Events Jonathan Fei. Definitions RANDOM EXPERIMENT: any procedure or situation that produces a definite outcome that may not.
Probability of Independent and Dependent Events and Review Probability & Statistics 1.0 Students know the definition of the notion of independent events.
STATISTIK LECTURE: AL MUIZZUDDIN F., SE., ME.. Key Concept In this section we present three different approaches to finding the probability of an event.
How likely something is to happen.
Probability of two events Example A coin is tossed twice. Draw a probability sample space diagram showing all the possible outcomes. What is the probability.
What is Probability? The study of probability helps us figure out the likelihood of something happening. In math we call this “something happening” or.
CORE 1 Patterns in Chance. Daily Starter Begin Handout.
1 Gold Silver Small set of drawers Three drawers, each with two coins.
Suppose you have 4 nickels, 2 dimes, and 6 quarters in your pocket. If you draw a coin randomly from your pocket, what is the probability that: a. You.
Jeopardy Final Jeopardy Definitions Prob Rules Tables Mixed Rules Mis- conceptions $100 $200 $300 $400 $500.
Probability Using Permutations and Combinations
Coach Combs Room 1150 Feel free to sit where there is a handout and begin filling it out.
Filling in a Venn diagram
7.3 Probabilities when Outcomes are Equally Likely.
Sets, Combinatorics, Probability, and Number Theory Mathematical Structures for Computer Science Chapter 3 Copyright © 2006 W.H. Freeman & Co.MSCS SlidesProbability.
Sets, Combinatorics, Probability, and Number Theory Mathematical Structures for Computer Science Chapter 3 Copyright © 2006 W.H. Freeman & Co.MSCS SlidesProbability.
Probabilities when Outcomes are Equally Likely. Math Message Which phrase – Extremely likely chance, or Very Unlikely best describes the chance.
HOMEWORK QUESTIONS?. 5.2 TWO-WAY TABLES PROBABILITY MODELS A probability model describes chance behavior by listing the possible outcomes in the sample.
How it really happen TAP 2. TAP Was a Cover Up TAP was a cover up to the truth but everyone says I the young ant am lying. Now I am on trial for lying.
Warm-up Day of Ch. 4 Test Suppose you flip a coin and then roll a die. a.Write out all the possible outcomes. b.Write the probability of all the possible.
Probability Probability is the measure of how likely an event is. An event is one or more outcomes of an experiment. An outcome is the result of a single.
Chapter 2: Rational Numbers 2.7 Probability of Compound Events.
Determining Probabilities Using Tree Diagrams and Tables.
PROBABILITY RULES – compound Events You roll two dice. What is the probability that you get a 5 on each die ?
Probability Introduction Examples Key words Practice questions Venn diagrams.
Probability Basics Section Starter Roll two dice and record the sum shown. Repeat until you have done 20 rolls. Write a list of all the possible.
Learn to find the probabilities of independent and dependent events. Course Independent and Dependent Events.
Math-Nuts Janie, Johnny, Jesse, Bob Introduction to Algebra and Geometry Fall 2011.
Pre-Algebra 9-7 Independent and Dependent Events Learn to find the probabilities of independent and dependent events.
Independent and Dependent Events. Independent Events Two events are independent if the outcome of one event does not affect the outcome of a second event.
5.2 Day One Probability Rules. Learning Targets 1.I can describe a probability model for a chance process. 2.I can use basic probability rules, including.
Lesson 4-6 Probability of Compound Events Objectives: To find the probability of independent and dependent events.
How likely it is that an event will occur the chance that a particular event will happen PROBABILITY.
Probability and Simulation The Study of Randomness.
No TISK Problems or Mental Math this week While Miss Wiltjer passes back your graded work from last quarter, you should fill out the “What I think it means”
Sullivan Algebra and Trigonometry: Section 14.3 Objectives of this Section Construct Probability Models Compute Probabilities of Equally Likely Outcomes.
How likely is something to happen..  When a coin is tossed, there are two possible outcomes: heads (H) or tails (T) We say the probability of a coin.
Sample Spaces and Probability Addition Rules Multiplication Rules and Conditional Probability Counting Rules Probability and Counting Rules
Probability. Definitions Probability: The chance of an event occurring. Probability Experiments: A process that leads to well- defined results called.
Probability What is the probability of rolling “snake eyes” in one roll? What is the probability of rolling “yahtzee” in one roll?
Westlake High School Science Department Course Offerings College Preparatory (CP) –Biology –Geoscience –Chemistry –Anatomy and Physiology –Marine Science.
Independent and Dependent Events. Learning Targets Determine when events are dependent or independent. Learn to use the multiplication rule of probability.
12.3 Probability of Equally Likely Outcomes
PROBABILLITY Transition Math.
= Basic Probability Notes Basics of Probability Probability
Career Guidance Washington Lesson 8-3
The 3 prisoners dilemma Inferring more complex values
Math 145 September 25, 2006.
I’m writing in first person. I’m going to tell you my story
5.2 Probability
Combining Probabilities
Filling in a Venn diagram
Combining Probabilities
If A and B are independent events, P (A and B) = P (A) P (B)
Lecture 22 Section 7.1 – Wed, Oct 20, 2004
Section 1.1: Equally Likely Outcomes
English Conversation 1 12/24 – 1/18.
Probability of two events
A plumbing contractor puts in bids on two large jobs
Almost Friday! Warm-Up… Quickwrite…
What does it really mean?
Additional Rule of Probability
Probability of two events
Chances, Probabilities, and Odds
Math 145 June 26, 2007.
Math 145 February 12, 2008.
Thursday 05/16 Warm Up 200 people were surveyed about ice cream preferences. 78 people said they prefer chocolate. 65 people said they prefer strawberry.
You pick a marble at random. What is the probability:
Sets, Combinatorics, Probability, and Number Theory
Presentation transcript:

Lecture 17 conditional probability Example : SARS Sample space, basic outcome, and event Basic rule A and B ( in both A and B) , A or B (in either A or B or both) Conditional probability of B given A =P{B|A}= P{A and B}/P{A} Probability of death for China Given a SARS death case, what is the probability that the case is from China?

Class enrollment : by year and by major Year : freshman, sophomore, junior, senior Major, life science, social science, math science,

Class enrollment : by year and by major Year : freshman, sophomore, junior, senior Major, life science, social science, math science, A=freshman, B=life science A and B = life science freshman P(A)=30%, P(B)=35%, P(A and B)=25% Find P(non-life science freshman) Randomly select a student. It turns out that he/she is not a freshman. What is the probability that he/she majors in life science?

Prisoner’s dilemma Three prisoners , A, B, C are in jail. One of them is to be executed and the other two will be set free. Prisoner A asked the guard : one of my partners B or C will be set free. Could you please tell me which one of them will be set free? Guard thought a while and told A : If I do not tell you, then your chance of death is 1/3. But if I tell you, then there are only two left and you are one of them to be killed. Your chance of death will be 1/2. Do you really want to increase your chance of death ?

Drawers A and B A has a good coin and a fake coin B has two good coins and a fake coin Open a drawer and pick a coin. Chance of getting fake one. Given the fake one is selected, what is the chance that it came from drawer A?