NUmerical measure of a likelihood of the occurrence of an event
Probability
What is the properties of an event occuring
0<=P(E)<=1
If an event cannot occur it is
P(E)=0
If the event occurs anytime it is
P(E)=1
WHa do you call the event that occurs when event a does not occur?
Complimentary probability
This is rule is based on the fact that the probability of an event and the probability of that event's complement must be rqual to 1
Complement Rule
P'(A)=1-P(A)
Complement rule
What are the two ways of assigning the probability of an event?
Classical probability and Empirical Probability
This type of probability is used to determine the probability associated with games of chance.
Classical approach
In this probability there are two assumptions(1) outcomes must be mutually exclusive (2) The outcomes are equally likely to occur
Classical approach
What is the formula for getting the probability of an event?
P(E)=n(E)/n(S) where n(E) is the number of occurence of event in sample space; n(s) is the cardinality of sample space
In the sequence of events, the total possible number of ways all events can be performed is the product of the possible number of each individual can be performed
Fundamental counting Principle
Arrangement of object without repetition and order is important
Permutation
Permutation formula where order is important
nPr=P(n,r)=n!/(n-r)1 where n is the total number of objects and r is the size of permutation
Arrangement of objects where order is not important
combination
Combination formula
nCr=n!/(n-r)!r!
method of finding probability that is based on cumulated historical data found through observations and not from theories
Empirical approach
Empirical Approach Formula
P(E)=n(E)/N where n(E) is the number of times the event has occured and N number of oppurtunities for an evet to occur
is a function that associates a real number with each sample point
Random variable
it is a rule that assigns probabilities to the random variables
Probability mass function
is another way of presenting probability distribution
Histogram
What are the two general classifications of probability distribution according to the nature of variables involved
discrete and continuous
defines probabilities that are associated with dicrete random variables
Discrete probability
Normal distribution is and example of what type of probability distribution
Continuous Probability Distribution
is a graphical representation of probability distribution
histogram
Is a rule that assigns probabilities to the values of the random variables
Probability Mass function
what denotes proability of failure in a single trial?
q
This rule states that the probability of a variable X that is greater than or equal to the given value x is equal to 1 minus the probability of less than or equal to a given value x minus 1
Complementary rule
Complementary rule formula
P(X>=x)=1=P(X<=[x-1])
Two balls are drawn in succession with replacement from an urn containing 5 red balls and 6 blue balls. Let Z be the random variable representing the number of blue balls.
Four coins are tossed. Let P be the random variable representing the number of heads that occur.
The sum of the probabilities in a probability distribution should always equal to one.
Histogram
Plots the values of the random variable along the horizontal axis and the probabilities along the vertical axis.
Random variable Y
0
1
2
3
Possible outcomes when 3 coins are tossed
HHH
HHT
HTH
HTT
THH
THT
TTH
TTT
The probability of each value of the random variable must be between or equal to 0 and 1.
The sum of the probabilities of all values of the random variable must be equal to 1.