The document discusses different types of study designs and sampling methods used in experiments and observational studies. It provides examples to identify the specific study design or sampling method used. Key points covered include: - Observational studies observe subjects without modifying outcomes, while experiments apply treatments to modify outcomes. - Random assignment of subjects to treatment and control groups allows for control of variables. - Sampling methods include random, systematic, stratified, cluster, and convenience.

1. Section 1.5 Chapter 1