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Breaking the Ice: Using Transparency to Overcome the Cold Start Problem in an Underground Market

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Marjanov, Tina 
Ioannidis, Konstantinos  ORCID logo
Hyndman, Tom 
Seyedzadeh, Nicolas 
Hutchings, Alice 


New users in anonymous underground marketplaces face the cold start problem; they have no reputation to signal their trustworthiness, hindering their ability to trade in the market. This study explores transparency, captured by the choice to make full contract details publicly visible to other users, as an overlooked trust signal. Analysing data from the Hack Forums marketplace, we find that transparency acts as a trust signal, primarily benefiting newcomers constrained by their lack of experience and reputation. However, as participants accumulate credibility, the importance of transparency wanes. Our findings underscore the dynamic nature of trust in such environments, highlighting the distinctive characteristics of private and public contracts as the market evolves.



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The 23rd Workshop on the Economics of Information Security

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The 23rd Workshop on the Economics of Information Security

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This work is supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 949127). Tina Marjanov is supported by King’s College, Cambridge and the Cambridge Trust. Konstantinos Ioannidis gratefully acknowledges support through the Leverhulme International Professorship in Neuroeconomics awarded to the University of Cambridge. Tom Hyndman and Nicolas Seyedzadeh were supported by the King’s College Summer Research Programme.