Probability Unit Vocabulary

Events for which the occurrence of one has no impact on the occurrence of the other.

All possible outcomes of a given experiment.

A subset of a sample space.

An event consisting of just one outcome. A simple event can be represented by a single branch of a tree diagram.

A sequence of simple events.

The complement of event E, sometimes denoted E’ (E prime), occurs when E doesn’t. The probability of E’ equals 1 minus the probability of

E: P(E’) = 1 – P(E).

If an event A can occur in m ways and for each of these m ways, an event B can occur in n ways, then events A and B can occur in m n ways. This counting principle can be generalized to more than two events that happen in succession. So, if for each of the m and n ways A and B can occur respectively, there is also an event C that can occur in s ways, then events A, B and C can occur in m n s ways.

A tree-shaped diagram that illustrates sequentially the possible outcomes of a given event.

The possible results of an experiment.

The chance something will happen.