The outcomes of an experiment are equally likely to occur when the probability of each outcome is equal.
For any sample space with N equally likely outcomes, we assign the probability to each outcome.
Examples of experiments with equally likely outcomes are:
- Draw a random sample of size n from a population or urn. The assumption that the sample is drawn at random means that all samples of size n have an equal chance of being chosen (much of statistical analysis depends on the assumption that samples are chosen randomly).
- Flip a fair coin n times and observe the sequence of heads an tails that results.
- Roll n dice, die 1, die 2, die 3, . . . , die n, and observe the ordered sequence of numbers on the uppermost faces.
Formula:
where,
f denotes the number of ways event E can occur,
N denotes the total number of outcomes possible,
P(E) denotes probability for equally likely outcomes
f denotes the number of ways event E can occur,
N denotes the total number of outcomes possible,
P(E) denotes probability for equally likely outcomes