The Silent Force: A Daily Diary Exploration of Affective Commitment, Optimism, and Engagement Among Iranian School Principals

Purpose: This study investigates the short-term psychological processes underlying school principals’ daily engagement. Drawing on affective events theory (AET), it examines how principals’ affective commitment at the end of a workday shapes their career optimism the following morning and how this optimism contributes to same-day work engagement (vigor, dedication, absorption). Research Methods: A five-day daily diary design was used with 119 school principals in Tehran, Iran. Participants completed surveys twice daily across consecutive workdays. Daily measures captured affective commitment (evening), career optimism (morning), and engagement dimensions (end-of-day). Hierarchical linear modeling was conducted to isolate within-person fluctuations from between-person differences, supplemented by mediation tests to evaluate temporal indirect effects. Findings: Affective commitment at the end of a workday significantly predicted higher career optimism the following morning. Career optimism, in turn, positively predicted daily absorption but did not significantly predict vigor or dedication. Affective commitment directly predicted all three engagement dimensions. Mediation analyses indicated that career optimism partially mediated the link between affective commitment and absorption, but not vigor or dedication. These findings highlight that principals’ emotional attachment to their school and their day-to-day cognitive expectations are dynamic intra-individual resources that meaningfully fluctuate from one day to the next. Implications: This study highlights the importance of examining principals’ psychological experiences as daily leadership resources. Strengthening principals’ affective commitment and fostering career optimism may enhance their capacity for focused, immersive engagement. Interventions oriented toward emotional connection, reflective practice, and future-focused professional development may help sustain principal engagement in demanding educational contexts.