Basic probability (Chapter4)

Complement of an A event

All outcomes that are not part of an event A. Example all dard that are not diamonds.

Statistically independent

If the outcome of event A is not affected by event B, then events A and B are said to be.

If P(A and B) = 0, then A and B must be

Mutually exclusive

If two equally likely events A and B are mutually exclusive and collectively exhaustive, what is the probability that event A williams occurr?

.50

Collection of all possible events is called

Sample space

If two events are mutually exclusive, what is the probability that both occur at the same time?

0

Cannot be determine

If two events are independent, what is the probability that they both occur?

Joint event

Involves two or more characteristics simutaneously. Example an ace that is also red from a deck of cards.

If events A and B cannot occur at the same time, then events A and B are said to be

Mutually exclusive

Collectively exhaustive events

One of the events must occur. The sample of events covers the entire sample space.

General Addition Rule

P(A or B) = P(A) + P(B) - P(A and B). If A and B are mutually exclusive the rule can be simplified to, P(A or B) = P(A) + P(B).

When in general multiplication rule, P(A and B) is equal

P(A\B) P(B)

If two events are collectively exhaustive, what is the probability that both occur at the same time.

Cannot be determine

Simple event

Event that can be described by a single characteristic.

If two events are collectively exhaustive, what is the probability that one or the other occurs?

1.0

Empirical Classic

Based on observed data. Probability of occurrence = # of favorable outcomes observed / total # of outcomes observed.

Probability

The chance that an uncertain event will occur. Always between 0 and 1.

Event

Each possible type of occurrence or outcome.

Mutually exclusive event

Events that cannot occur together (simultaneously). Example: B=having a boy, G=having a girl. Events B and G are mutually exclusive if only one child is born.

Subjective Probability

Probability of an event based on an individuals past experience, personal opinion, and or analysis of a particular situation

Priori Classical Probability

Probability of an event based on prior knowledge of the process involved. Probability of occurrence = # of ways event can occurr / total number of possible outcomes.

Events in a sample space

Simple event, an outcome from a sample space with one characteristic. Example a red card from a deck of cards.

Marginal

Simple probability is also called

Sample space

The collection of all possible events. Example all 52 catds in a deck of cards and all possible outcomes when having a child: boy or girl.