The Impostor Phenomenon and the Confidence Gap

The Impostor Phenomenon (IP) and the Confidence Gap describe gendered differences in self-assessment and perceived competence, with well-documented implications for learning, retention, and performance. While each has been studied independently, little research has investigated how these phenomena interact -- particularly within computing education contexts. This study addresses the gap by examining the relationship between IP and confidence among university students in web software development courses in Northern Europe. Drawing on 392 survey responses, we analyze how IP and self-reported confidence vary with gender, degree level, and prior programming experience, and expanding prior work, how these constructs relate to one another. Our findings confirm previously reported patterns -- women report higher IP and lower confidence than men -- and provide new insights: confidence partially mediates the relationship between gender and IP, indicating that lower confidence may partially help explain gender disparities in IP. Furthermore, while programming experience predicts confidence, its relationship to IP is more nuanced. Experience has a small direct positive effect on IP that is largely offset by an indirect confidence-driven reduction. These findings suggest that impostor feelings are shaped more by self-perception than skill, and they highlight the need for interventions that focus on both skill development and psychological support.