Although extensive research has examined social media nudges to influence privacy, comparably less work investigates mechanisms of peer-to-peer influence, or the ways in which peer groups can amplify or dampen privacy considerations. This study takes an experimental approach to examining how people are influenced to share potentially sensitive photos of others without consent---a common practice on social media---by comparing the effects of encouraging, discouraging, or mixed feedback social media comments. The results show that discouraging peer comments reduce the sharing of others' photos when content portrayed targets negatively. However, peer influence backfired among users with a history of online misconduct, with both encouraging and discouraging comments leading to more photo sharing. Moreover, a mix of comments that both discouraged and encouraged sharing led to the highest levels of sharing. Linking to prior work, this research establishes a broader understanding of when privacy nudges are likely to backfire on social media: for users with past online misconduct and when information goes against social norms. The findings advance understanding of how peer-to-peer dynamics shape online information flows and highlight the complex effects of Web-based social feedback on privacy decisions. These insights provide actionable design recommendations for platforms to foster responsible, privacy-conscious sharing norms.

We collected and analyzed Instagram direct messages (DMs) from 173 youth aged 13–21 (including 86 LGBTQ+ youth). We examined youth’s risk-flagged social media trace data with their self-reported mental health outcomes to examine how the differing online experiences of LGBTQ+ youth compare with their heterosexual counterparts. We found that LGBTQ+ youth experienced significantly more high-risk online interactions compared to heterosexual youth. LGBTQ+ youth reported overall poorer mental health, with online harassment specifically amplifying Self-Harm and Injury. LGBTQ+ youth’s mental well-being linked positively to sexual messages, unlike heterosexual youth. Qualitatively, we found that most of the risk-flagged messages of LGBTQ+ youth were sexually motivated; however, a silver lining was that they sought support for their sexual identity from peers on the platform. The study highlights the importance of tailored online safety and inclusive design for LGBTQ+ youth, with implications for CHI community advancements in fostering a supportive online environments.

Although a great deal of research has examined interventions to help users protect their own information online, less work has examined methods for reducing interdependent privacy (IDP) violations on social media (i.e., sharing of other people's information). This study tested the effectiveness of concept-based (i.e., general information), fact-based (i.e., statistics), and narrative-based (i.e., stories) educational videos in altering IDP-relevant attitudes and multimedia sharing behaviors. Our study revealed concept and fact videos reduced sharing of social media content that portrayed people negatively. The narrative intervention backfired and increased sharing among participants who did not believe IDP violations to be especially serious; however, the narrative intervention decreased sharing for participants who rated IDP violations as more serious. Notably, our study found participants preferred narrative-based interventions with real world examples, despite other strategies more effectively reducing sharing. Implications for narrative transportation theory and advancing bottom-up (i.e., user-centered) psychosocial interventions are discussed.

Interdependent privacy (IDP) violations occur when users share personal information about others without permission, resulting in potential embarrassment, reputation loss, or harassment. There are several strategies that can be applied to protect IDP, but little is known regarding how social media users perceive IDP threats or how they prefer to respond to them. We utilized a mixed-method approach with a replication study to examine user beliefs about various government-, platform-, and user-level strategies for managing IDP violations. Participants reported that IDP represented a 'serious' online threat, and identified themselves as primarily responsible for responding to violations. IDP strategies that felt more familiar and provided greater perceived control over violations (e.g., flagging, blocking, unfriending) were rated as more effective than platform or government driven interventions. Furthermore, we found users were more willing to share on social media if they perceived their interactions as protected. Findings are discussed in relation to control paradox theory.