The pervasive adoption of digital payment systems globally is a crucial development, shaping the financial landscapes of diverse nations. However, this surge in adoption has precipitated a concerning rise in cybercrimes. This prompts users to reassess preferred payment modes and occasionally...

In virtual worlds of MMORPGs (Massively Multiplayer Online Role-Playing Games), we observe that many players purchase virtual items by using real currencies, which is so-called eBaying. Extending the model developed by Castronova (2001), I analyze the value of virtual items in the virtual and...

A game between a representative household and a government was analyzed. The household chose which fractions of two currencies to hold, e.g., a national currency such as a Central Bank Digital Currency (CBDC) and a global currency such as Bitcoin or Facebook's Diem, and chose the tax evasion...

We explore the interaction between central bank digital currencies and cryptocurrencies using a game-theoretic model. The solution of this model is characterized by a multiplicity of equilibria, delimited by the regulatory capability of the central bank and its interaction with the financial...