This document provides an overview of topics to be covered in Week 4 of a Museum Research Methods course, including a review of concepts, assignments, and focus readings. It introduces the topics of confounding variables, the difference between correlation and causation, and issues of sample selection and size to ensure a representative sample. Key concepts are that confounding variables can obscure the relationship between two variables, correlation does not necessarily imply causation, and samples must be selected and sized properly to represent the whole population.