Probability refers to the likelihood or chance of an event occurring. It is a measure of uncertainty and is typically represented as a number between 0 and 1, where 0 indicates impossibility (an event will not occur) and 1 indicates certainty (an event will occur). The higher the probability of an event, the more likely it is to happen.
Types of probabilities include:
Classical Probability:- Classical probability is based on equally likely outcomes in a sample space. It assumes that each outcome has the same chance of occurring.
Empirical Probability:-Empirical probability is based on observed data or experiments. It involves collecting data and calculating the relative frequency of an event occurring.
Subjective Probability:-Subjective probability is based on personal judgment or beliefs about the likelihood of an event occurring. It does not rely on historical data or mathematical calculations but rather on an individual’s opinions, experiences, or intuition.
Conditional Probability:-Conditional probability measures the likelihood of an event occurring given that another event has already occurred. It is denoted by ๐(๐ดโฃ๐ต)P(AโฃB), where ๐ดA is the event of interest and ๐ตB is the condition. For example, the probability of drawing a red card from a deck of cards given that a card drawn was a face card would be a conditional probability.
Joint Probability:-Joint probability refers to the probability of two or more events occurring simultaneously. It is denoted by ๐(๐ดโฉ๐ต)P(AโฉB), where ๐ดA and ๐ตB are the events of interest. For example, the joint probability of rolling a 3 on a fair six-sided die and flipping a coin and getting heads would be a joint probability.
Marginal Probability:-Marginal probability refers to the probability of a single event occurring without considering any other events. It is obtained by summing or averaging over all possible outcomes of the other events. For example, the marginal probability of rolling an even number on a fair six-sided die would consider all possible outcomes that result in an even number (2, 4, or 6).
Related topics
- Introduction to statistics
- Grouped and ungrouped data
- Histograms
- Measures of Central tendency
- Mean for grouped data
- Working with the assumed mean
- Quartiles, Deciles and percentiles
- Measures of dispersion
- Variance