Nonequilibrium phase transitions in competitive markets caused by network effects

Area of Science:

• Economic Theory
• Agent-Based Modeling
• Statistical Physics

Background:

• Network effects, where product value increases with popularity, are crucial in economic markets.
• Conventional microeconomics often assumes perfect competition, which may not hold with strong network effects.

Purpose of the Study:

• To develop a minimal theory of competitive markets with demand-side network effects for indistinguishable goods.
• To investigate the market dynamics and phase transitions resulting from increasing network effects.

Main Methods:

• Utilized agent-based models inspired by statistical physics principles.
• Simulated a competitive market with statistically identical sellers and demand-side network effects.

Main Results:

• Weak network effects yield a steady state of near-perfect competition.
• Increasing network effects trigger a phase transition to a nonequilibrium phase characterized by fad formation and collapse.
• Rapid price updates by sellers can lead to emergent monopolies, breaking market symmetry and ergodicity.

Conclusions:

• The model explains empirically observed phenomena like price fluctuations, persistent profits, and broad market share distributions.
• Network effects fundamentally alter market dynamics, moving beyond standard competitive models.
• The study highlights the emergence of complex behaviors from simple market rules under network effects.