 Odds ratio

The odds ratio is the ratio of two event odds. For rare events it is close to the corresponding risk ratio, because $p/(1-p)\simeq p$ when $p$ is small.

The odds ratio (OR) is a statistic that quantifies the strength of the association between two events, commonly used in epidemiology and various fields of research. It compares the odds of an event occurring in one group to the odds of it occurring in another group. Here's how it works: 1. **Definition of Odds**: The odds of an event is the ratio of the probability that the event occurs to the probability that it does not occur.