A hypothetical study predicting individuals' willingness to have unprotected sex based on their measured mood (positive versus negative) and self-esteem (high versus low) exemplifies a non-experimental factorial design. This study is conceptualized as a $2 imes 2$ factorial design with mood and self-esteem serving as non-manipulated between-subjects factors. Because neither independent variable is actively manipulated by the researcher, the study cannot establish causality.