160 likes | 265 Views
Chapter 6 Section 2. Experiments, Outcomes, and Events. Basic Definitions. Experiment: An activity with an observable outcome. Trial: The act of performing a single experiment. Outcome: The observable result of the experiment. Sample Space (S). Sample Space:
E N D
Chapter 6 Section 2 Experiments, Outcomes, and Events
Basic Definitions • Experiment: An activity with an observable outcome. • Trial: The act of performing a single experiment. • Outcome: The observable result of the experiment.
Sample Space (S) • Sample Space: • The set of all possible outcomes of the experiment. • Set should be chosen so that there is no overlap • S = { ‘list of all possible outcomes’ } • You can think of the sample space as the universal set for the experiments.
Events • Event: A set that is a subset of the sample space. • Impossible Event: An event that cannot occur. • i.e. The outcome is not in the sample space. • Denoted using the symbol: Ø
Exercise 5 (page 270) • Situation: Two urns, each containing several balls. Both urns contain some red balls and some white balls. ? ? ? ? ? ? ? ? ? ? ? ? Urn I Urn II
Exercise 5 Notation Definition Let : • I represent Urn I • II represent Urn II • R represent a Red Ball • W represent a White Ball Experiment: Pick one of the two urns and then draw a ball from the urn that is picked.
Exercise 5 Part (a) • What is a suitable sample space for this experiment? • Possible Solution: S = { ( I , R ) , ( I , W ) , ( II , R ) , ( II , W) }
Exercise 5 Part (b) • Describe the event “Urn I is selected” E = { ( I , R ) , ( I , W ) }
For events E and F • The event E F occurs precisely when either event E or event F (or both) occur. • The event E F occurs precisely when both events E and event F occur.
Other relationships: • Event E occurs when event E does not occur. • E E = S • E E = • Two events are mutually exclusive (or disjoint) events when: E F =
Exercise 7 (page 270) • Efficiency expert records the time that it takes an assembly line worker to perform a particular task. • Let event… E = { more than five minutes } F = { less than eight minutes } G = { less than four minutes }
Exercise 7 (part a) • Describe the sample space for this experiment. S = { all positive numbers of minutes }
Exercise 7 (part b) Describe the following: • E F E F = { more than 5 minutes but less than 8 minutes } • E G E G = • E E = { 5 minutes or less }
Exercise 7 (part b) continued Describe the following: 4. E F E F = {5 minutes or less } 5. E F G E F G = { less than 4 minutes } 6. E F E F = S
Exercise 17 (page 271) • Toss a coin 10 times and observe the number of heads. • Sample space? S = { 0 , 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 } • Describe the event E of “more than 5 heads” in terms of the sample space. E = { 6 , 7 , 8 , 9 , 10 }
Exercise 3(page 270) Toss a coin twice and observe the sequence of heads (H) and tails (T). • Define the sample space: S = { HH , HT , TH , TT } • The first toss is a head: E = { HH , HT}