BANA 2081 EXAM 2 CH. 4-6 STUDY GUIDE
random experiment - Answer -A random experiment is a process that generates well-
defined experimental outcomes. On any single repetition or trial, the outcome that
occurs is determined completely by chance.
sample space - Answer -the set of all possible outcomes
sample point - Answer -An element of the sample space. A sample point represents an
experimental outcome.
multiple-step experiment - Answer -an experiment described as a sequence of k steps
with n1 possible outcomes on the first step, n2 possible outcomes on second step, and
so on, then total number of experimental outcomes is given by (n1)(n2)(n3)...(nk)
tree diagram (probability) - Answer -a diagram used to show the total number of
possible outcomes in an experiment
Combinations - Answer -n!/r!(n-r)!
order does not matter
r=# of objects
n= # selected
permutations - Answer -an arrangement or listing in which an order or placement is
important
r!/(r-n)!
Basic requirements for assigning probabilities - Answer -1. The probability assigned to
each experimental outcome must be between 0 and 1
2. The sum of the probabilities for all experimental outcomes must equal 1
classical method - Answer -a method of assigning probabilities that is appropriate when
all the experimental outcomes are equally likely
relative frequency method - Answer -a method of assigning probabilities that is
appropriate when data are available to estimate the proportion of the time the
experimental outcome will occur if the experiment is repeated a large number of times
subjective method - Answer -a method of assigning probabilities on the basis of
judgment
event - Answer -a collection of sample points
, Probability of an Event - Answer -the sum of the probabilities of the sample points in
the event
complement of an event - Answer -consists of all possible outcomes in a sample space
that are NOT part of the event
denoted by A^c
Venn Diagram - Answer -A diagram that is used to show relationships between sets.
P(A)+P(A^c)= - Answer -1
P(A)=1-P(A^c) - Answer -computing probability using the complement
Union of two events - Answer -The union of events A and B is the event containing all
sample points that are in A or B or both
Intersection of two events - Answer -The intersection of events A and B is the set of all
sample points that are in both A and B
Addition Law - Answer -a probability law used to compute the probability of the union of
two events
P(AuB=P(A)+P(B)-P(AnB)
mutually exclusive events - Answer -events that have no sample points in common
addition law for mutually exclusive events - Answer -P(AuB)=P(A)+P(B)
Conditional Probability - Answer -the probability that one event happens given that
another event is already known to have happened
Joint Probability - Answer -the probability of the intersection of two events
marginal probabilities - Answer -The values in the margins of the joint probability table,
which provide the probability of each event separately.
Conditional Probability Formula - Answer -P(A|B) = P(A and B) / P(B)
or
P(B|A) = P(A and B) / P(A)
independent events - Answer -The outcome of one event does not affect the outcome
of the second event
independent events formula - Answer -P(A | B) = P(A) and P(B | A) = P(B)
random experiment - Answer -A random experiment is a process that generates well-
defined experimental outcomes. On any single repetition or trial, the outcome that
occurs is determined completely by chance.
sample space - Answer -the set of all possible outcomes
sample point - Answer -An element of the sample space. A sample point represents an
experimental outcome.
multiple-step experiment - Answer -an experiment described as a sequence of k steps
with n1 possible outcomes on the first step, n2 possible outcomes on second step, and
so on, then total number of experimental outcomes is given by (n1)(n2)(n3)...(nk)
tree diagram (probability) - Answer -a diagram used to show the total number of
possible outcomes in an experiment
Combinations - Answer -n!/r!(n-r)!
order does not matter
r=# of objects
n= # selected
permutations - Answer -an arrangement or listing in which an order or placement is
important
r!/(r-n)!
Basic requirements for assigning probabilities - Answer -1. The probability assigned to
each experimental outcome must be between 0 and 1
2. The sum of the probabilities for all experimental outcomes must equal 1
classical method - Answer -a method of assigning probabilities that is appropriate when
all the experimental outcomes are equally likely
relative frequency method - Answer -a method of assigning probabilities that is
appropriate when data are available to estimate the proportion of the time the
experimental outcome will occur if the experiment is repeated a large number of times
subjective method - Answer -a method of assigning probabilities on the basis of
judgment
event - Answer -a collection of sample points
, Probability of an Event - Answer -the sum of the probabilities of the sample points in
the event
complement of an event - Answer -consists of all possible outcomes in a sample space
that are NOT part of the event
denoted by A^c
Venn Diagram - Answer -A diagram that is used to show relationships between sets.
P(A)+P(A^c)= - Answer -1
P(A)=1-P(A^c) - Answer -computing probability using the complement
Union of two events - Answer -The union of events A and B is the event containing all
sample points that are in A or B or both
Intersection of two events - Answer -The intersection of events A and B is the set of all
sample points that are in both A and B
Addition Law - Answer -a probability law used to compute the probability of the union of
two events
P(AuB=P(A)+P(B)-P(AnB)
mutually exclusive events - Answer -events that have no sample points in common
addition law for mutually exclusive events - Answer -P(AuB)=P(A)+P(B)
Conditional Probability - Answer -the probability that one event happens given that
another event is already known to have happened
Joint Probability - Answer -the probability of the intersection of two events
marginal probabilities - Answer -The values in the margins of the joint probability table,
which provide the probability of each event separately.
Conditional Probability Formula - Answer -P(A|B) = P(A and B) / P(B)
or
P(B|A) = P(A and B) / P(A)
independent events - Answer -The outcome of one event does not affect the outcome
of the second event
independent events formula - Answer -P(A | B) = P(A) and P(B | A) = P(B)
