Survival Analysis

Overview

Survival analysis studies time until an event occurs, handling censored data where events haven't happened for some subjects, enabling prediction of lifetimes and risk assessment.

Key Concepts

• Survival Time: Time until event
• Censoring: Event not observed (subject dropped out)
• Hazard: Instantaneous risk at time t
• Survival Curve: Probability of surviving past time t
• Hazard Ratio: Relative risk between groups

Common Models

• Kaplan-Meier: Non-parametric survival curves
• Cox Proportional Hazards: Semi-parametric regression
• Weibull/Exponential: Parametric models