Probability theory fundamentals
2 min readDec 10, 2022
Probability theory is a branch of mathematics that deals with the analysis of random phenomena. It’s used to model and predict the likelihood of different outcomes in a wide variety of situations, from games of chance to the behavior of subatomic particles.
Some of the key concepts in probability theory include:
- Sample space: This is the set of all possible outcomes of a random event. For example, in a coin toss, the sample space would be the set {of heads, tails}.
- Probability: This is a measure of the likelihood of an outcome occurring. Probability is always a number between 0 and 1, where 0 indicates that an outcome is impossible and 1 indicates that an outcome is certain.
- Independence: This refers to the idea that the outcome of one event does not affect the outcome of another event. For example, the outcome of a coin toss is independent of the outcome of a dice roll.
- Complementary events: These are events that cannot both occur at the same time. For example, in a coin toss, the event “heads” is complementary to the event “tails”.
- Additive rule: This states that the probability of two events occurring together is the sum of the probabilities of each event occurring separately. For example, the probability of flipping a coin and rolling a die and getting heads…