Probability-Theory

• Countable set: it consists of countable number (finite or countably infinite) of elements. For example, the set of even numbers is countably infinite; the set of prime numbers under 10,000 is finite.

• Uncountable set: it consists of uncountable number of elements. For example, the number of real numbers in any interval (a, b); the set of possible outcomes from measuring human weight or height.

Experiments

• Many investigations may be characterized in part by the fact that repeated experimentation.
• Each experiment terminates with an outcome.
• Suppose that we have such an experiment, the outcome of which can’t be predicted.
• If this kind of experiment can be repeated under the same conditions, it is called a random experiment.
• The collection of every possible outcome is called the experimental space or the sample space.
• Event – a set of outcomes.