SOSina Ostendorf

Sina Ostendorf

*This is an algorithmically generated author record based on publicly available information.

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Sina Ostendorf has a total of 11 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Theoretical conceptualization of online privacy-related decision making – Introducing the tripartite self-disclosure decision model

    by Sina Ostendorf, Matthias Brand

    Self-disclosures on online social networks have received increased attention in the last two decades. Researchers from different disciplines investigated manifold influencing variables, and studies applied different theories to explain why many users share very sensitive and personal information despite potential risks and negative consequences, whereas others do not. Oftentimes, it is argued that self-disclosure decisions result from a kind of rational “calculus” of risks and benefits. However, such an assumption of rationality can and has been criticized. Nevertheless, fundamental cognitive and affective mechanisms that underlie self-disclosure decision making on social networks are still under-explored. By building upon previous self-disclosure theories and models, dual-and tripartite-system perspectives of decision making, and former empirical findings, we propose a Tripartite Self-Disclosure Decision (TSDD) model that conceptualizes inner processes of online self-disclosure decision making. Central to this model is the proposed interaction of three neural and cognitive/affective systems: a reflective, an impulsive, and an interoceptive system. We further highlight individual and environmental features, which can impact individuals’ online self-disclosure decisions by (interactively) influencing the proposed inner decision-making processes targeting the aforementioned three systems. Possible short- and long-term consequences are also discussed, which in turn can affect certain model components in subsequent self-disclosure decision situations. By taking such a neurocognitive perspective, we expand current research and models, which helps to better understand potentially risky information sharing on online social networks and can support attempts to prevent users from incautious self-disclosures.


  • Open Access

    Self-disclosure on social networks: More than a rational decision-making process

    by Sina Ostendorf, Yannic Meier, Matthias Brand

    Although consequences of sharing personal information can be negative and severe (e.g., identity theft), individuals still engage in extensive self-disclosures on social networks. One commonly applied explanatory approach is the privacy calculus. Following this, self-disclosures can be conceptualized as rational choices resulting from a weighing of risks and benefits. However, this view misses the additional impulsive nature of decisions. The current study therefore takes the lens of dual-process theories and highlights that self-disclosure decisions can also be guided by an impulsive system. To test for the impact of descriptive social norms, a warning message, privacy-related decision-making styles, and perceived benefits and risks on individuals’ self-disclosure decisions, the fictitious social network “AHOY!” was created. It enabled the measurement of participants’ (N = 551; Mage = 40.77, SDage = 13.93) actual self-disclosures on two decision stages: 1) whether or not a post was created, 2) how much information (on a psychological and informational dimension) was provided. Further, descriptive social norms (i.e., the extent of other users’ self-disclosures) and the presence/absence of a warning message were varied. The remaining factors were measured using questionnaires. The results imply that cognitive and affective processes (expected to be triggered by the investigated factors) are involved differently in the two decision stages. While both the reflective and impulsive system may be involved in the first stage, with the reflective system also potentially taking a predominant role, the impulsive system may be predominant when deciding how much to disclose. This highlights the importance of exceeding common assumptions of rationality to better understand and support individuals’ self-disclosure decisions.


  • Open Access

    Neglecting Long-Term Risks: Self-Disclosure on Social Media and Its Relation to Individual Decision-Making Tendencies and Problematic Social-Networks-Use

    by Sina Ostendorf, Silke M. Müller, Matthias Brand

    Social media including social-networking sites (SNS) encourage people to disclose personal information via profiles and posts. It is assumed that positive short-term effects and immediate feedback (e.g., getting Likes) have a rewarding nature and may complicate the rational weighing of possible negative long-term consequences related to self-disclosure. Dual-process theories assume risky behaviors to result from more impulsive/short-term oriented compared to reflective/long-term oriented decision making. The current laboratory study investigates whether the extent of online self-disclosure is explained by the general tendency to choose short-term rewards by neglecting long-term risks as well as by tendencies toward a problematic social-networks-use. Participants (N = 88) were asked to log into their Facebook account to answer questions about their actual self-disclosing behavior. Furthermore, they performed an experimental decision-making task and answered a questionnaire assessing problematic social-networks-use. The quantity of self-disclosure via posts was negatively associated with advantageous decision making and positively with tendencies toward a problematic social-networks-use. The findings indicate that high self-disclosure via posts is associated with a general tendency to neglect long-term risks. Moreover, a problematic social-networks-use can additionally increase individual’s self-disclosure via posts.


  • Open Access

    Problematic Social-Networks-Use in German Children and Adolescents—The Interaction of Need to Belong, Online Self-Regulative Competences, and Age

    by Sina Ostendorf, Elisa Wegmann, Matthias Brand

    Adolescents nowadays spend much time communicating via social networks. Recent investigations also report a noticeable proportion showing a problematic usage behavior, underlining the importance of better understanding its development and maintenance in young individuals. Theoretical views on Internet-use disorders assume that specific predispositions and needs can contribute to addictive behaviors in interaction with further aspects including Internet-related cognitive biases. This study focuses on vulnerable individuals due to their age and investigates interactions between possible risk (need to belong, NTB) and protective factors (online self-regulative competences, OSRC). Participants (N = 466) between 10 and 17 years answered questionnaires assessing social-networks-use disorder symptoms, NTB, and OSRC. Moderated regression analysis revealed significant effects of age, NTB, and OSRC. Three-way interaction was also significant (potentially mainly caused by females), with highest social-networks-use disorder symptoms found for individuals with high NTB and low OSRC, especially when older. With high OSRC, symptoms were significantly lower for both younger and older individuals having high NTB. However, even if NTB was low, older individuals showed high social-networks-use disorder symptoms if their OSRC were low. The results highlight the importance of improving specific competences to prevent problematic usage behaviors, which should be considered in youth-tailored prevention and intervention programs.