 Proportional hazards model

A proportional hazards model writes $h(t\mid z)=h_0(t)r(z)$, so covariates multiply the baseline hazard by a ratio that does not depend on time.

The proportional hazards model, often referred to as Cox proportional hazards model, is a type of regression model commonly used in survival analysis. It is primarily designed to examine the effect of various predictors or covariates on the time it takes for a particular event to occur, such as death, failure, or any other time-to-event outcome.