The survival of products in online services such as Google Play, Yelp, Facebook and Amazon, is contingent on their search rank. This, along with the social impact of such services, has also turned them into a lucrative medium for fraudulently influencing public opinion. Motivated by the need to aggressively promote products, communities that specialize in social network fraud (e.g., fake opinions and reviews, likes, followers, app installs) have emerged, to create a black market for fraudulent search optimization. Fraudulent product developers exploit these communities to hire teams of workers willing and able to commit fraud collectively, emulating realistic, spontaneous activities from unrelated people. We call this behavior “search rank fraud”. In this dissertation, we argue that fraud needs to be proactively discouraged and prevented, instead of only reactively detected and filtered. We introduce two novel approaches to discourage search rank fraud in online systems. First, we detect fraud in real-time, when it is posted, and impose resource consuming penalties on the devices that post activities. We introduce and leverage several novel concepts that include (i) stateless, verifiable computational puzzles that impose minimal performance overhead, but enable the efficient verification of their authenticity, (ii) a real-time, graph based solution to assign fraud scores to user activities, and (iii) mechanisms to dynamically adjust puzzle difficulty levels based on fraud scores and the computational capabilities of devices. In a second approach, we introduce the problem of fraud de-anonymization: reveal the crowdsourcing site accounts of the people who post large amounts of fraud, thus their bank accounts, and provide compelling evidence of fraud to the users of products that they promote. We investigate the ability of our solutions to ensure that fraud does not pay off.

Background: Despite a slight decline in the prevalence of substance use among adolescents in last years, there is a constant need for effective, available and well-targeted preventive interventions. Children of parents with substance use experiences are considered to be more endangered. Although the quality and availability of universal prevention programs has improved, their effectiveness is not usually systematically verified, moreover, the impact on children of parents with substance use experiences is unknown. The Unplugged preventive intervention was supplemented by nPrevention booster sessions in order to support its research-proven preventive impact. Aims: The main objective was to evaluate the effect of Unplugged and nPrevention programs combination (Un+nP) after 24 months in comparison with Unplugged program (Un) alone and control in respect of the substance use experience in parents. The secondary objective was to test the reliability of anonymous self-generated identification code (SGIC) and the process of matching children's questionnaires between waves of data collection and with parents' questionnaires. Methods: A cluster randomized, controlled, 3-arm, prospective, school-based prevention trial was conducted between years 2013 and 2017 to evaluate the Unplugged (implemented in the 6th...

Social loafing is a phenomenon where individuals exert less effort in a group than when working alone. Social loafing has been widely examined through experimental studies, primarily conducted on face-to-face teams. The recent COVID-19 pandemic changed the working patterns around the world, increasing the amount of remote work in our society. This shift in working patterns resurfaces social loafing as an important area of research. Understanding the relationships between social loafing and its factors is important for increasing individual team members' efforts. This bachelor’s thesis aims to fill knowledge gaps by investigating the relationships between social loafing and the key factors explaining it. This research draws upon social identity and media richness theory to explain the relationships between individuals and groups and the role of communication mediums. Based on previous literature, we developed hypotheses concerning the effects of team size, cohesion, anonymity, and virtuality on social loafing. The findings reveal a significant correlation between team size, cohesion, and social loafing. Anonymity and virtuality showed no statistical significance with social loafing. Overall, the findings contribute to our understanding of key factors influencing social loafing. Future research is needed to explore the impact of these factors as well as additional factors that may contribute to the phenomenon that this study did not acknowledge. / Social medåkning är ett fenomen som karaktäriseras av att individer lägger ner mindre ansträngning när de arbetar i grupp än när de arbetar på egen hand. Social medåkning har studerats noggrant genom experimentella studier, främst på grupper som träffas fysiskt. Den senaste Covid-19-pandemin tiden förändrade arbetsmönstren runt i världen, vilket ökade mängden distansarbete i samhället. Distansarbete kan vara i sin tur att leda till social loafing genom att minska motivation och engagemang. Det är viktigt att förstå relationerna mellan social medåkning och dess faktorer för att öka prestationen hos gruppmedlemmar. Forskningen bygger på teorierna om “social identity” och “media richness” för att förklara relationerna mellan individer och grupper samt rollen hos kommunikationsmedier. Vi har utvecklat hypoteser om effekterna av gruppstorlek, sammanhållning, anonymitet och virtualitet baserade på tidigare litteratur. Detta kandidatarbete syftar till att undersöka relationerna mellan social medåkning och dess faktorer såsom gruppstorlek, sammanhållning, anonymitet och virtualitet för att förbättra prestationen i grupparbete. Resultaten visade på en signifikant korrelation mellan gruppstorlek, sammanhållning och social medåkning. Dessutom finns en signifikant korrelation mellan anonymitet och sammanhållning. Sammanfattningsvis bidrar forskningen till en ökad förståelse för de viktigaste faktorerna som påverkar social medåkning. Resultaten betonade vikten av gruppstorlek och sammanhållning, vilket pekar på att anonymitet och virtualitet kan ha begränsad effekt. Framtida forskning bör utforska inverkan av dessa faktorer samt ytterligare faktorer som kan bidra till fenomenet som denna studie ännu inte har uppmärksammat.

This study examines the intricate dynamics of online anonymity in the context of Fishbrain, a platform for fishing enthusiasts. By conducting semi-structured interviews with ten Fishbrain users, I scrutinized the experiences and understanding of online anonymity through a deductive thematic analysis approach. This research was further underpinned by a comprehensive platform analysis. Using Eklund et al.'s framework [15], I studied six themes that encompass both macro and micro-regulating structures that govern online anonymity. The research findings highlight the pivotal role of these structures, revealing that users frequently balance the advantages of disclosing personal information against potential risks. This study accentuates the need to consider a spectrum of factors—commercial, legal, and technological structures, alongside the factual, social group, and physical facets of anonymity—when investigating online anonymity. This research expands the existing body of knowledge on online anonymity and provides valuable insights for platforms like Fishbrain to better address their users' concerns and customize their features and policies effectively.

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This thesis explores data anonymization techniques within the context of a Swedish municipality with a focus on safeguarding data privacy, enhancement of decision-making, and assessing re-identification risks. The investigation, grounded in a literature review and an experimental study, employed the ARX anonymization tool on a sample municipality employee database. Three distinct human resource management (HRM) datasets, analogous to the employee database, were created and anonymized using the ARX tool to ascertain the efficacy and re-identification risks of the employed techniques.  A key finding indicates an inverse relationship between dataset size and re-identification risk, enhancing data utility with larger datasets. This suggests that larger datasets are more conducive to anonymization, motivating organizations to engage in anonymization efforts for internal analytics and open data publishing.  The study contributes to Information Security discourse, emphasizing the criticality of data anonymization in preserving privacy and ensuring data utility in the era of big data. The research faced constraints due to privacy considerations, necessitating the use of similar, rather than actual, datasets, potentially affecting the results and limiting full representation for future techniques. The thesis primarily addresses HRM applications, indicating the scope for future research into other municipal or organizational governance areas. In conclusion, it underscores the necessity of data anonymization in the face of tightening regulations and sophisticated privacy breaches. This positions the organization strategically for compliance, minimizes data breach risks and upholds anonymization as a fundamental principle of Information Security.

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All around Stockholm, housing is under construction. But the theme is not housing - it is variation. Varied facades, varied roofscapes, to create variation along the streets. I propose that there is a safety in monotony - the kind that is lacking on the housing market. Anonymity can be a sign that the sender had you in mind, rather than themselves; this was the best we could do, therefore we repeated it over and over again, implying there is a ”we” and not an ”I” behind it all. This that is provided for you - for example a home - is not something you must earn, it can be taken for granted, by you and everyone else. Nya Hjorthagen is an alternative proposal for the site of Norra Djurgårdsstaden.

Humans have found ways to communicate with each other since the beginning of time. However, the way we communicate has changed over the years. Today we can communicate with people from all over the world by employing digital technologies, and this can sometimes be done without revealing individuals’ actual identity. With anonymity comes many problems, such as a lack of responsibility, the feelings of other people seem to be valued lower in an online setting than in the real world, and there are often no consequences for those who behave badly or unethically. This study investigates how our morals correlate with our degree of anonymity while we communicate in an online setting. To achieve the study’s goal, a social experiment, where participants had the choice to act either altruistic or selfish, was performed. The social experiment was in the form of an online competition and was conducted under two different conditions. In the first clause, the participants were completely anonymous and in the second, they were exposed with their full names and a picture with their face visible. The hypothesis for the study was that a higher level of anonymity reduces the feeling of responsibility, which causes a person to care less about her moral compass, and will therefore make more selfish choices. The results showed that this was not the case. A higher percentage chose the selfish option when presented with name and picture. However, the result also exhibited that the majority of the study participants felt a difference in their behaviour during the two clauses. / Människor har hittat sätt att kommunicera med varandra så länge människor har funnits på jorden, men sättet vi kommunicerar på har förändrats över tid. De senaste decennierna har denna förändring skett på en helt ny nivå. Idag kan vi kommunicera med personer över hela världen, och detta utan att nödvändigtvis avslöja vår identitet. Med denna möjlighet till anonymitet kommer många problem, såsom en brist på ansvar för ens egna handlingar. Det är lätt att dela sina åsikter och att bete sig dåligt. I de fall där våra ideer och åsikter sårar en annan person, finns det sällan något som kräver att vi ska ta konsekvenserna för våra handlingar. Denna studie undersökte om det fanns ett samband mellan förändring i vår moral och vår grad av anonymitet. Detta gjordes genom ett socialt experiment där deltagarna fick möjligheten att vara givmilda eller själviska. Det sociala experimentet skedde i form av en tävling online, två matcher under två olika förutsättningar. I den första matchen var deltagarna helt anonyma och i den andra var de presenterade med fullständigt namn och profilbild med synligt ansikte. Hypotesen för studien var att en högre grad av anonymitet minskar känslan av ansvar, vilket i sin tur får personen att ta mer själviska beslut. Resultatet från det sociala experimentet visade att så inte var fallet. En högre procent av deltagarna valde det själviska alternativet när de var presenterade med namn och bild. Resultaten visade dock även att en majoritet av deltagarna kände sig påverkade av sin grad av anonymitet, men inte tillräckligt att det skulle påverka deras beslut.

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