This document discusses key concepts in social science research including:
1. Theory provides explanations for phenomena while concepts refer to shared characteristics. Operational definitions concisely define concepts for measurement.
2. Variables are characteristics that can vary and are classified as independent, dependent, or antecedent. Hypotheses predict relationships between independent and dependent variables.
3. Causality is difficult to establish as many factors can influence outcomes. Alternative explanations must be eliminated to make causal claims.