AI engineering glossary · Probability
What is likelihood?
Likelihood (also called Likelihood function): How probable the observed data are for a particular value of a model's parameter, treated as a function of that parameter with the data held fixed. Unlike a probability distribution, it does not need to sum to 1 over parameter values.
Likelihood: an example
If a coin lands heads 7 times in 10 tosses, the likelihood at p = 0.7 is much higher than at p = 0.3.
Related terms
More Probability terms
- Linearity of expectation
- Marginal distribution
- Marginal probability
- Markov chain
- Markov chain Monte Carlo
- Markov property
- Markov's inequality
- Maximum likelihood estimation
Where you learn it
Likelihood is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.