additional 2 Flashcards
What is probability
a numerical measure of the likelihood that an event will occur
What can probability be used for
used as measures of the degree of uncertainty
probability values are always assigned on a scale of
0 to 1
what is a prob of near zero indicate
event is unlikely to occur
what is prob of near 1 indicate
an event is almost certain to occur
what is an experiment
a process that generates well-defined outcomes
what is a sample space
set of all experimental outcomes
what is an experimental outcome also called
a sample point
what is a sample point
identifies an element of the sample space
What is the counting rule for a multistep experiment
if an experiment can be described as a sequence of k steps with n1 possible outcomes on the first step, n2 possible outcomes on the second step, and so on
What is a tree diagram
a graphical representation that helps us visualize the multi-step experiment
In a tree diagram, along the branches you
multiply
What are the 3 useful Counting Rules
- Multistep experiment
- Combinations
- Permutations
What are combinations
- allows us to count the # of experimental outcomes when the experiment involves select n objects for a set of N objects and ORDER DOES NOT MATTER
What are permutations
- allows us to compute the # of experimental outcomes when n objects are to be selected from a set of N objects and ORDER MATTERS
Does permutations or combinations result in more
permutations
b/c every selection of n objects can be ordered in n! different ways
What are the 3 most useful approaches for assigning probabilities
- Classical Method
- Relative Frequency method
- Subjective method
Explain classical method
use when: all experimental outcome are EQUALLY LIKELY
- the 2 basic requirements are satisfied
- example tossing a coin
Explain when to use the Relative Freq. Method
use when: data re available to estimate PROPROTION Of TIME and the experimental outcome will occur if the experiment is REPEATED a LARGE # of TIMES
- 2 basic requirements are satisfied
Explain when you would use the Subjective Method
Use When: we CANNOT realistically assume that the experimental outcomes are Equally Likely and when Little relevant data is available - degree of belief
Which method would we use Bayes Theorem for
Subjective method
what are the basic requirements for assigning Probabilities
- the prob assigned to each experimental outcome must be b/w 0 and 1 inclusively
- Sum of prob for all experimental outcomes must equal 1.0
What is an event
collection of sample points