Hierarchical Linear Modeling

Hierarchical linear modeling (HLM; also known as multilevel modeling or MLM) is a statistical method that can be used when data are “nested,” such that participants or their responses or scores on a certain variable can be grouped in a meaningful way. Specifically, nested data refers to the situation in which lower-level units of data are nested within higher-level units of data. For example, students can be nested in classes (which are then nested in schools), employees can be nested within organizations, and romantic partners can be nested in couples. HLM is very useful in communication research, which focuses on issues that involve more than one person (e.g., romantic relationships or decision-making groups). By providing a way to quantitatively study groups of people, HLM can ...